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Slavery in the United States

Jenny Bourne, Carleton College

Slavery is fundamentally an economic phenomenon. Throughout history, slavery has existed where it has been economically worthwhile to those in power. The principal example in modern times is the U.S. South. Nearly 4 million slaves with a market value of close to $4 billion lived in the U.S. just before the Civil War. Masters enjoyed rates of return on slaves comparable to those on other assets; cotton consumers, insurance companies, and industrial enterprises benefited from slavery as well. Such valuable property required rules to protect it, and the institutional practices surrounding slavery display a sophistication that rivals modern-day law and business.


Not long after Columbus set sail for the New World, the French and Spanish brought slaves with them on various expeditions. Slaves accompanied Ponce de Leon to Florida in 1513, for instance. But a far greater proportion of slaves arrived in chains in crowded, sweltering cargo holds. The first dark-skinned slaves in what was to become British North America arrived in Virginia — perhaps stopping first in Spanish lands — in 1619 aboard a Dutch vessel. From 1500 to 1900, approximately 12 million Africans were forced from their homes to go westward, with about 10 million of them completing the journey. Yet very few ended up in the British colonies and young American republic. By 1808, when the trans-Atlantic slave trade to the U.S. officially ended, only about 6 percent of African slaves landing in the New World had come to North America.

Slavery in the North

Colonial slavery had a slow start, particularly in the North. The proportion there never got much above 5 percent of the total population. Scholars have speculated as to why, without coming to a definite conclusion. Some surmise that indentured servants were fundamentally better suited to the Northern climate, crops, and tasks at hand; some claim that anti-slavery sentiment provided the explanation. At the time of the American Revolution, fewer than 10 percent of the half million slaves in the thirteen colonies resided in the North, working primarily in agriculture. New York had the greatest number, with just over 20,000. New Jersey had close to 12,000 slaves. Vermont was the first Northern region to abolish slavery when it became an independent republic in 1777. Most of the original Northern colonies implemented a process of gradual emancipation in the late eighteenth and early nineteenth centuries, requiring the children of slave mothers to remain in servitude for a set period, typically 28 years. Other regions above the Mason-Dixon line ended slavery upon statehood early in the nineteenth century — Ohio in 1803 and Indiana in 1816, for instance.

Population of the Original Thirteen Colonies, selected years by type

1750 1750 1790 1790 1790 1810 1810 1810 1860 1860 1860


White Black White Free Slave White Free Slave White Free Slave
Nonwhite Nonwhite Nonwhite
108,270 3,010 232,236 2,771 2,648 255,179 6,453 310 451,504 8,643 - Connecticut
27,208 1,496 46,310 3,899 8,887 55,361 13,136 4,177 90,589 19,829 1,798 Delaware
4,200 1,000 52,886 398 29,264 145,414 1,801 105,218 591,550 3,538 462,198 Georgia
97,623 43,450 208,649 8,043 103,036 235,117 33,927 111,502 515,918 83,942 87,189 Maryland
183,925 4,075 373,187 5,369 - 465,303 6,737 - 1,221,432 9,634 - Massachusetts
26,955 550 141,112 630 157 182,690 970 - 325,579 494 - New Hampshire
66,039 5,354 169,954 2,762 11,423 226,868 7,843 10,851 646,699 25,318 - New Jersey
65,682 11,014 314,366 4,682 21,193 918,699 25,333 15,017 3,831,590 49,145 - New York
53,184 19,800 289,181 5,041 100,783 376,410 10,266 168,824 629,942 31,621 331,059 North Carolina
116,794 2,872 317,479 6,531 3,707 786,804 22,492 795 2,849,259 56,956 - Pennsylvania
29,879 3,347 64,670 3,484 958 73,214 3,609 108 170,649 3,971 - Rhode Island
25,000 39,000 140,178 1,801 107,094 214,196 4,554 196,365 291,300 10,002 402,406 South Carolina
129,581 101,452 442,117 12,866 292,627 551,534 30,570 392,518 1,047,299 58,154 490,865 Virginia
934,340 236,420 2,792,325 58,277 681,777 4,486,789 167,691 1,005,685 12,663,310 361,247 1,775,515 United States

Source: Historical Statistics of the U.S. (1970), Franklin (1988).

Slavery in the South

Throughout colonial and antebellum history, U.S. slaves lived primarily in the South. Slaves comprised less than a tenth of the total Southern population in 1680 but grew to a third by 1790. At that date, 293,000 slaves lived in Virginia alone, making up 42 percent of all slaves in the U.S. at the time. South Carolina, North Carolina, and Maryland each had over 100,000 slaves. After the American Revolution, the Southern slave population exploded, reaching about 1.1 million in 1810 and over 3.9 million in 1860.

Population of the South 1790-1860 by type

Year White Free Nonwhite Slave
1790 1,240,454 32,523 654,121
1800 1,691,892 61,575 851,532
1810 2,118,144 97,284 1,103,700
1820 2,867,454 130,487 1,509,904
1830 3,614,600 175,074 1,983,860
1840 4,601,873 207,214 2,481,390
1850 6,184,477 235,821 3,200,364
1860 8,036,700 253,082 3,950,511

Source: Historical Statistics of the U.S. (1970).

Slave Ownership Patterns

Despite their numbers, slaves typically comprised a minority of the local population. Only in antebellum South Carolina and Mississippi did slaves outnumber free persons. Most Southerners owned no slaves and most slaves lived in small groups rather than on large plantations. Less than one-quarter of white Southerners held slaves, with half of these holding fewer than five and fewer than 1 percent owning more than one hundred. In 1860, the average number of slaves residing together was about ten.

Slaves as a Percent of the Total Population
selected years, by Southern state

1750 1790 1810 1860
State Black/total Slave/total Slave/total Slave/total
population population population population
Alabama 45.12
Arkansas 25.52
Delaware 5.21 15.04 5.75 1.60
Florida 43.97
Georgia 19.23 35.45 41.68 43.72
Kentucky 16.87 19.82 19.51
Louisiana 46.85
Maryland 30.80 32.23 29.30 12.69
Mississippi 55.18
Missouri 9.72
North Carolina 27.13 25.51 30.39 33.35
South Carolina 60.94 43.00 47.30 57.18
Tennessee 17.02 24.84
Texas 30.22
Virginia 43.91 39.14 40.27 30.75
Overall 37.97 33.95 33.25 32.27

Sources: Historical Statistics of the United States (1970), Franklin (1988).

Holdings of Southern Slaveowners
by states, 1860

State Total Held 1 Held 2 Held 3 Held 4 Held 5 Held 1-5 Held 100- Held 500+
slaveholders slave slaves Slaves slaves slaves slaves 499 slaves slaves
AL 33,730 5,607 3,663 2,805 2,329 1,986 16,390 344 -
AR 11,481 2,339 1,503 1,070 894 730 6,536 65 1
DE 587 237 114 74 51 34 510 - -
FL 5,152 863 568 437 365 285 2,518 47 -
GA 41,084 6,713 4,335 3,482 2,984 2,543 20,057 211 8
KY 38,645 9,306 5,430 4,009 3,281 2,694 24,720 7 -
LA 22,033 4,092 2,573 2,034 1,536 1,310 11,545 543 4
MD 13,783 4,119 1,952 1,279 1,023 815 9,188 16 -
MS 30,943 4,856 3,201 2,503 2,129 1,809 14,498 315 1
MO 24,320 6,893 3,754 2,773 2,243 1,686 17,349 4 -
NC 34,658 6,440 4,017 3,068 2,546 2,245 18,316 133 -
SC 26,701 3,763 2,533 1,990 1,731 1,541 11,558 441 8
TN 36,844 7,820 4,738 3,609 3,012 2,536 21,715 47 -
TX 21,878 4,593 2,874 2,093 1,782 1,439 12,781 54 -
VA 52,128 11,085 5,989 4,474 3,807 3,233 28,588 114 -
TOTAL 393,967 78,726 47,244 35,700 29,713 24,886 216,269 2,341 22

Source: Historical Statistics of the United States (1970).

Rapid Natural Increase in U.S. Slave Population

How did the U.S. slave population increase nearly fourfold between 1810 and 1860, given the demise of the trans-Atlantic trade? They enjoyed an exceptional rate of natural increase. Unlike elsewhere in the New World, the South did not require constant infusions of immigrant slaves to keep its slave population intact. In fact, by 1825, 36 percent of the slaves in the Western hemisphere lived in the U.S. This was partly due to higher birth rates, which were in turn due to a more equal ratio of female to male slaves in the U.S. relative to other parts of the Americas. Lower mortality rates also figured prominently. Climate was one cause; crops were another. U.S. slaves planted and harvested first tobacco and then, after Eli Whitney’s invention of the cotton gin in 1793, cotton. This work was relatively less grueling than the tasks on the sugar plantations of the West Indies and in the mines and fields of South America. Southern slaves worked in industry, did domestic work, and grew a variety of other food crops as well, mostly under less abusive conditions than their counterparts elsewhere. For example, the South grew half to three-quarters of the corn crop harvested between 1840 and 1860.


Central to the success of slavery are political and legal institutions that validate the ownership of other persons. A Kentucky court acknowledged the dual character of slaves in Turner v. Johnson (1838): “[S]laves are property and must, under our present institutions, be treated as such. But they are human beings, with like passions, sympathies, and affections with ourselves.” To construct slave law, lawmakers borrowed from laws concerning personal property and animals, as well as from rules regarding servants, employees, and free persons. The outcome was a set of doctrines that supported the Southern way of life.

The English common law of property formed a foundation for U.S. slave law. The French and Spanish influence in Louisiana — and, to a lesser extent, Texas — meant that Roman (or civil) law offered building blocks there as well. Despite certain formal distinctions, slave law as practiced differed little from common-law to civil-law states. Southern state law governed roughly five areas: slave status, masters’ treatment of slaves, interactions between slaveowners and contractual partners, rights and duties of noncontractual parties toward others’ slaves, and slave crimes. Federal law and laws in various Northern states also dealt with matters of interstate commerce, travel, and fugitive slaves.

Interestingly enough, just as slave law combined elements of other sorts of law, so too did it yield principles that eventually applied elsewhere. Lawmakers had to consider the intelligence and volition of slaves as they crafted laws to preserve property rights. Slavery therefore created legal rules that could potentially apply to free persons as well as to those in bondage. Many legal principles we now consider standard in fact had their origins in slave law.

Legal Status Of Slaves And Blacks

By the end of the seventeenth century, the status of blacks — slave or free — tended to follow the status of their mothers. Generally, “white” persons were not slaves but Native and African Americans could be. One odd case was the offspring of a free white woman and a slave: the law often bound these people to servitude for thirty-one years. Conversion to Christianity could set a slave free in the early colonial period, but this practice quickly disappeared.

Skin Color and Status

Southern law largely identified skin color with status. Those who appeared African or of African descent were generally presumed to be slaves. Virginia was the only state to pass a statute that actually classified people by race: essentially, it considered those with one quarter or more black ancestry as black. Other states used informal tests in addition to visual inspection: one-quarter, one-eighth, or one-sixteenth black ancestry might categorize a person as black.

Even if blacks proved their freedom, they enjoyed little higher status than slaves except, to some extent, in Louisiana. Many Southern states forbade free persons of color from becoming preachers, selling certain goods, tending bar, staying out past a certain time of night, or owning dogs, among other things. Federal law denied black persons citizenship under the Dred Scott decision (1857). In this case, Chief Justice Roger Taney also determined that visiting a free state did not free a slave who returned to a slave state, nor did traveling to a free territory ensure emancipation.

Rights And Responsibilities Of Slave Masters

Southern masters enjoyed great freedom in their dealings with slaves. North Carolina Chief Justice Thomas Ruffin expressed the sentiments of many Southerners when he wrote in State v. Mann (1829): “The power of the master must be absolute, to render the submission of the slave perfect.” By the nineteenth century, household heads had far more physical power over their slaves than their employees. In part, the differences in allowable punishment had to do with the substitutability of other means of persuasion. Instead of physical coercion, antebellum employers could legally withhold all wages if a worker did not complete all agreed-upon services. No such alternate mechanism existed for slaves.

Despite the respect Southerners held for the power of masters, the law — particularly in the thirty years before the Civil War — limited owners somewhat. Southerners feared that unchecked slave abuse could lead to theft, public beatings, and insurrection. People also thought that hungry slaves would steal produce and livestock. But masters who treated slaves too well, or gave them freedom, caused consternation as well. The preamble to Delaware’s Act of 1767 conveys one prevalent view: “[I]t is found by experience, that freed [N]egroes and mulattoes are idle and slothful, and often prove burdensome to the neighborhood wherein they live, and are of evil examples to slaves.” Accordingly, masters sometimes fell afoul of the criminal law not only when they brutalized or neglected their slaves, but also when they indulged or manumitted slaves. Still, prosecuting masters was extremely difficult, because often the only witnesses were slaves or wives, neither of whom could testify against male heads of household.

Law of Manumission

One area that changed dramatically over time was the law of manumission. The South initially allowed masters to set their slaves free because this was an inherent right of property ownership. During the Revolutionary period, some Southern leaders also believed that manumission was consistent with the ideology of the new nation. Manumission occurred only rarely in colonial times, increased dramatically during the Revolution, then diminished after the early 1800s. By the 1830s, most Southern states had begun to limit manumission. Allowing masters to free their slaves at will created incentives to emancipate only unproductive slaves. Consequently, the community at large bore the costs of young, old, and disabled former slaves. The public might also run the risk of having rebellious former slaves in its midst.

Antebellum U.S. Southern states worried considerably about these problems and eventually enacted restrictions on the age at which slaves could be free, the number freed by any one master, and the number manumitted by last will. Some required former masters to file indemnifying bonds with state treasurers so governments would not have to support indigent former slaves. Some instead required former owners to contribute to ex-slaves’ upkeep. Many states limited manumissions to slaves of a certain age who were capable of earning a living. A few states made masters emancipate their slaves out of state or encouraged slaveowners to bequeath slaves to the Colonization Society, which would then send the freed slaves to Liberia. Former slaves sometimes paid fees on the way out of town to make up for lost property tax revenue; they often encountered hostility and residential fees on the other end as well. By 1860, most Southern states had banned in-state and post-mortem manumissions, and some had enacted procedures by which free blacks could voluntarily become slaves.

Other Restrictions

In addition to constraints on manumission, laws restricted other actions of masters and, by extension, slaves. Masters generally had to maintain a certain ratio of white to black residents upon plantations. Some laws barred slaves from owning musical instruments or bearing firearms. All states refused to allow slaves to make contracts or testify in court against whites. About half of Southern states prohibited masters from teaching slaves to read and write although some of these permitted slaves to learn rudimentary mathematics. Masters could use slaves for some tasks and responsibilities, but they typically could not order slaves to compel payment, beat white men, or sample cotton. Nor could slaves officially hire themselves out to others, although such prohibitions were often ignored by masters, slaves, hirers, and public officials. Owners faced fines and sometimes damages if their slaves stole from others or caused injuries.

Southern law did encourage benevolence, at least if it tended to supplement the lash and shackle. Court opinions in particular indicate the belief that good treatment of slaves could enhance labor productivity, increase plantation profits, and reinforce sentimental ties. Allowing slaves to control small amounts of property, even if statutes prohibited it, was an oft-sanctioned practice. Courts also permitted slaves small diversions, such as Christmas parties and quilting bees, despite statutes that barred slave assemblies.

Sale, Hire, And Transportation Of Slaves

Sales of Slaves

Slaves were freely bought and sold across the antebellum South. Southern law offered greater protection to slave buyers than to buyers of other goods, in part because slaves were complex commodities with characteristics not easily ascertained by inspection. Slave sellers were responsible for their representations, required to disclose known defects, and often liable for unknown defects, as well as bound by explicit contractual language. These rules stand in stark contrast to the caveat emptor doctrine applied in antebellum commodity sales cases. In fact, they more closely resemble certain provisions of the modern Uniform Commercial Code. Sales law in two states stands out. South Carolina was extremely pro-buyer, presuming that any slave sold at full price was sound. Louisiana buyers enjoyed extensive legal protection as well. A sold slave who later manifested an incurable disease or vice — such as a tendency to escape frequently — could generate a lawsuit that entitled the purchaser to nullify the sale.

Hiring Out Slaves

Slaves faced the possibility of being hired out by their masters as well as being sold. Although scholars disagree about the extent of hiring in agriculture, most concur that hired slaves frequently worked in manufacturing, construction, mining, and domestic service. Hired slaves and free persons often labored side by side. Bond and free workers both faced a legal burden to behave responsibly on the job. Yet the law of the workplace differed significantly for the two: generally speaking, employers were far more culpable in cases of injuries to slaves. The divergent law for slave and free workers does not necessarily imply that free workers suffered. Empirical evidence shows that nineteenth-century free laborers received at least partial compensation for the risks of jobs. Indeed, the tripartite nature of slave-hiring arrangements suggests why antebellum laws appeared as they did. Whereas free persons had direct work and contractual relations with their bosses, slaves worked under terms designed by others. Free workers arguably could have walked out or insisted on different conditions or wages. Slaves could not. The law therefore offered substitute protections. Still, the powerful interests of slaveowners also may mean that they simply were more successful at shaping the law. Postbellum developments in employment law — North and South — in fact paralleled earlier slave-hiring law, at times relying upon slave cases as legal precedents.

Public Transportation

Public transportation also figured into slave law: slaves suffered death and injury aboard common carriers as well as traveled as legitimate passengers and fugitives. As elsewhere, slave-common carrier law both borrowed from and established precedents for other areas of law. One key doctrine originating in slave cases was the “last-clear-chance rule.” Common-carrier defendants that had failed to offer slaves — even negligent slaves — a last clear chance to avoid accidents ended up paying damages to slaveowners. Slaveowner plaintiffs won several cases in the decade before the Civil War when engineers failed to warn slaves off railroad tracks. Postbellum courts used slave cases as precedents to entrench the last-clear-chance doctrine.

Slave Control: Patrollers And Overseers

Society at large shared in maintaining the machinery of slavery. In place of a standing police force, Southern states passed legislation to establish and regulate county-wide citizen patrols. Essentially, Southern citizens took upon themselves the protection of their neighbors’ interests as well as their own. County courts had local administrative authority; court officials appointed three to five men per patrol from a pool of white male citizens to serve for a specified period. Typical patrol duty ranged from one night per week for a year to twelve hours per month for three months. Not all white men had to serve: judges, magistrates, ministers, and sometimes millers and blacksmiths enjoyed exemptions. So did those in the higher ranks of the state militia. In many states, courts had to select from adult males under a certain age, usually 45, 50, or 60. Some states allowed only slaveowners or householders to join patrols. Patrollers typically earned fees for captured fugitive slaves and exemption from road or militia duty, as well as hourly wages. Keeping order among slaves was the patrollers’ primary duty. Statutes set guidelines for appropriate treatment of slaves and often imposed fines for unlawful beatings. In rare instances, patrollers had to compensate masters for injured slaves. For the most part, however, patrollers enjoyed quasi-judicial or quasi-executive powers in their dealings with slaves.

Overseers commanded considerable control as well. The Southern overseer was the linchpin of the large slave plantation. He ran daily operations and served as a first line of defense in safeguarding whites. The vigorous protests against drafting overseers into military service during the Civil War reveal their significance to the South. Yet slaves were too valuable to be left to the whims of frustrated, angry overseers. Injuries caused to slaves by overseers’ cruelty (or “immoral conduct”) usually entitled masters to recover civil damages. Overseers occasionally confronted criminal charges as well. Brutality by overseers naturally generated responses by their victims; at times, courts reduced murder charges to manslaughter when slaves killed abusive overseers.

Protecting The Master Against Loss: Slave Injury And Slave Stealing

Whether they liked it or not, many Southerners dealt daily with slaves. Southern law shaped these interactions among strangers, awarding damages more often for injuries to slaves than injuries to other property or persons, shielding slaves more than free persons from brutality, and generating convictions more frequently in slave-stealing cases than in other criminal cases. The law also recognized more offenses against slaveowners than against other property owners because slaves, unlike other property, succumbed to influence.

Just as assaults of slaves generated civil damages and criminal penalties, so did stealing a slave to sell him or help him escape to freedom. Many Southerners considered slave stealing worse than killing fellow citizens. In marked contrast, selling a free black person into slavery carried almost no penalty.

The counterpart to helping slaves escape — picking up fugitives — also created laws. Southern states offered rewards to defray the costs of capture or passed statutes requiring owners to pay fees to those who caught and returned slaves. Some Northern citizens worked hand-in-hand with their Southern counterparts, returning fugitive slaves to masters either with or without the prompting of law. But many Northerners vehemently opposed the peculiar institution. In an attempt to stitch together the young nation, the federal government passed the first fugitive slave act in 1793. To circumvent its application, several Northern states passed personal liberty laws in the 1840s. Stronger federal fugitive slave legislation then passed in 1850. Still, enough slaves fled to freedom — perhaps as many as 15,000 in the decade before the Civil War — with the help (or inaction) of Northerners that the profession of “slave-catching” evolved. This occupation was often highly risky — enough so that such men could not purchase life insurance coverage — and just as often highly lucrative.

Slave Crimes

Southern law governed slaves as well as slaveowners and their adversaries. What few due process protections slaves possessed stemmed from desires to grant rights to masters. Still, slaves faced harsh penalties for their crimes. When slaves stole, rioted, set fires, or killed free people, the law sometimes had to subvert the property rights of masters in order to preserve slavery as a social institution.

Slaves, like other antebellum Southern residents, committed a host of crimes ranging from arson to theft to homicide. Other slave crimes included violating curfew, attending religious meetings without a master’s consent, and running away. Indeed, a slave was not permitted off his master’s farm or business without his owner’s permission. In rural areas, a slave was required to carry a written pass to leave the master’s land.

Southern states erected numerous punishments for slave crimes, including prison terms, banishment, whipping, castration, and execution. In most states, the criminal law for slaves (and blacks generally) was noticeably harsher than for free whites; in others, slave law as practiced resembled that governing poorer white citizens. Particularly harsh punishments applied to slaves who had allegedly killed their masters or who had committed rebellious acts. Southerners considered these acts of treason and resorted to immolation, drawing and quartering, and hanging.


Market prices for slaves reflect their substantial economic value. Scholars have gathered slave prices from a variety of sources, including censuses, probate records, plantation and slave-trader accounts, and proceedings of slave auctions. These data sets reveal that prime field hands went for four to six hundred dollars in the U.S. in 1800, thirteen to fifteen hundred dollars in 1850, and up to three thousand dollars just before Fort Sumter fell. Even controlling for inflation, the prices of U.S. slaves rose significantly in the six decades before South Carolina seceded from the Union. By 1860, Southerners owned close to $4 billion worth of slaves. Slavery remained a thriving business on the eve of the Civil War: Fogel and Engerman (1974) projected that by 1890 slave prices would have increased on average more than 50 percent over their 1860 levels. No wonder the South rose in armed resistance to protect its enormous investment.

Slave markets existed across the antebellum U.S. South. Even today, one can find stone markers like the one next to the Antietam battlefield, which reads: “From 1800 to 1865 This Stone Was Used as a Slave Auction Block. It has been a famous landmark at this original location for over 150 years.” Private auctions, estate sales, and professional traders facilitated easy exchange. Established dealers like Franklin and Armfield in Virginia, Woolfolk, Saunders, and Overly in Maryland, and Nathan Bedford Forrest in Tennessee prospered alongside itinerant traders who operated in a few counties, buying slaves for cash from their owners, then moving them overland in coffles to the lower South. Over a million slaves were taken across state lines between 1790 and 1860 with many more moving within states. Some of these slaves went with their owners; many were sold to new owners. In his monumental study, Michael Tadman (1989) found that slaves who lived in the upper South faced a very real chance of being sold for profit. From 1820 to 1860, he estimated that an average of 200,000 slaves per decade moved from the upper to the lower South, most via sales. A contemporary newspaper, The Virginia Times, calculated that 40,000 slaves were sold in the year 1830.

Determinants of Slave Prices

The prices paid for slaves reflected two economic factors: the characteristics of the slave and the conditions of the market. Important individual features included age, sex, childbearing capacity (for females), physical condition, temperament, and skill level. In addition, the supply of slaves, demand for products produced by slaves, and seasonal factors helped determine market conditions and therefore prices.

Age and Price

Prices for both male and female slaves tended to follow similar life-cycle patterns. In the U.S. South, infant slaves sold for a positive price because masters expected them to live long enough to make the initial costs of raising them worthwhile. Prices rose through puberty as productivity and experience increased. In nineteenth-century New Orleans, for example, prices peaked at about age 22 for females and age 25 for males. Girls cost more than boys up to their mid-teens. The genders then switched places in terms of value. In the Old South, boys aged 14 sold for 71 percent of the price of 27-year-old men, whereas girls aged 14 sold for 65 percent of the price of 27-year-old men. After the peak age, prices declined slowly for a time, then fell off rapidly as the aging process caused productivity to fall. Compared to full-grown men, women were worth 80 to 90 percent as much. One characteristic in particular set some females apart: their ability to bear children. Fertile females commanded a premium. The mother-child link also proved important for pricing in a different way: people sometimes paid more for intact families.

Source: Fogel and Engerman (1974)

Other Characteristics and Price

Skills, physical traits, mental capabilities, and other qualities also helped determine a slave’s price. Skilled workers sold for premiums of 40-55 percent whereas crippled and chronically ill slaves sold for deep discounts. Slaves who proved troublesome — runaways, thieves, layabouts, drunks, slow learners, and the like — also sold for lower prices. Taller slaves cost more, perhaps because height acts as a proxy for healthiness. In New Orleans, light-skinned females (who were often used as concubines) sold for a 5 percent premium.

Fluctuations in Supply

Prices for slaves fluctuated with market conditions as well as with individual characteristics. U.S. slave prices fell around 1800 as the Haitian revolution sparked the movement of slaves into the Southern states. Less than a decade later, slave prices climbed when the international slave trade was banned, cutting off legal external supplies. Interestingly enough, among those who supported the closing of the trans-Atlantic slave trade were several Southern slaveowners. Why this apparent anomaly? Because the resulting reduction in supply drove up the prices of slaves already living in the U.S and, hence, their masters’ wealth. U.S. slaves had high enough fertility rates and low enough mortality rates to reproduce themselves, so Southern slaveowners did not worry about having too few slaves to go around.

Fluctuations in Demand

Demand helped determine prices as well. The demand for slaves derived in part from the demand for the commodities and services that slaves provided. Changes in slave occupations and variability in prices for slave-produced goods therefore created movements in slave prices. As slaves replaced increasingly expensive indentured servants in the New World, their prices went up. In the period 1748 to 1775, slave prices in British America rose nearly 30 percent. As cotton prices fell in the 1840s, Southern slave prices also fell. But, as the demand for cotton and tobacco grew after about 1850, the prices of slaves increased as well.

Interregional Price Differences

Differences in demand across regions led to transitional regional price differences, which in turn meant large movements of slaves. Yet because planters experienced greater stability among their workforce when entire plantations moved, 84 percent of slaves were taken to the lower South in this way rather than being sold piecemeal.

Time of Year and Price

Demand sometimes had to do with the time of year a sale took place. For example, slave prices in the New Orleans market were 10 to 20 percent higher in January than in September. Why? September was a busy time of year for plantation owners: the opportunity cost of their time was relatively high. Prices had to be relatively low for them to be willing to travel to New Orleans during harvest time.

Expectations and Prices

One additional demand factor loomed large in determining slave prices: the expectation of continued legal slavery. As the American Civil War progressed, prices dropped dramatically because people could not be sure that slavery would survive. In New Orleans, prime male slaves sold on average for $1381 in 1861 and for $1116 in 1862. Burgeoning inflation meant that real prices fell considerably more. By war’s end, slaves sold for a small fraction of their 1860 price.

Source: Data supplied by Stanley Engerman and reported in Walton and Rockoff (1994).


That slavery was profitable seems almost obvious. Yet scholars have argued furiously about this matter. On one side stand antebellum writers such as Hinton Rowan Helper and Frederick Law Olmstead, many antebellum abolitionists, and contemporary scholars like Eugene Genovese (at least in his early writings), who speculated that American slavery was unprofitable, inefficient, and incompatible with urban life. On the other side are scholars who have marshaled masses of data to support their contention that Southern slavery was profitable and efficient relative to free labor and that slavery suited cities as well as farms. These researchers stress the similarity between slave markets and markets for other sorts of capital.

Consensus That Slavery Was Profitable

This battle has largely been won by those who claim that New World slavery was profitable. Much like other businessmen, New World slaveowners responded to market signals — adjusting crop mixes, reallocating slaves to more profitable tasks, hiring out idle slaves, and selling slaves for profit. One well-known instance shows that contemporaneous free labor thought that urban slavery may even have worked too well: employees of the Tredegar Iron Works in Richmond, Virginia, went out on their first strike in 1847 to protest the use of slave labor at the Works.

Fogel and Engerman’s Time on the Cross

Carrying the banner of the “slavery was profitable” camp is Nobel laureate Robert Fogel. Perhaps the most controversial book ever written about American slavery is Time on the Cross, published in 1974 by Fogel and co-author Stanley Engerman. These men were among the first to use modern statistical methods, computers, and large datasets to answer a series of empirical questions about the economics of slavery. To find profit levels and rates of return, they built upon the work of Alfred Conrad and John Meyer, who in 1958 had calculated similar measures from data on cotton prices, physical yield per slave, demographic characteristics of slaves (including expected lifespan), maintenance and supervisory costs, and (in the case of females) number of children. To estimate the relative efficiency of farms, Fogel and Engerman devised an index of “total factor productivity,” which measured the output per average unit of input on each type of farm. They included in this index controls for quality of livestock and land and for age and sex composition of the workforce, as well as amounts of output, labor, land, and capital

Time on the Cross generated praise — and considerable criticism. A major critique appeared in 1976 as a collection of articles entitled Reckoning with Slavery. Although some contributors took umbrage at the tone of the book and denied that it broke new ground, others focused on flawed and insufficient data and inappropriate inferences. Despite its shortcomings, Time on the Cross inarguably brought people’s attention to a new way of viewing slavery. The book also served as a catalyst for much subsequent research. Even Eugene Genovese, long an ardent proponent of the belief that Southern planters had held slaves for their prestige value, finally acknowledged that slavery was probably a profitable enterprise. Fogel himself refined and expanded his views in a 1989 book, Without Consent or Contract.

Efficiency Estimates

Fogel’s and Engerman’s research led them to conclude that investments in slaves generated high rates of return, masters held slaves for profit motives rather than for prestige, and slavery thrived in cities and rural areas alike. They also found that antebellum Southern farms were 35 percent more efficient overall than Northern ones and that slave farms in the New South were 53 percent more efficient than free farms in either North or South. This would mean that a slave farm that is otherwise identical to a free farm (in terms of the amount of land, livestock, machinery and labor used) would produce output worth 53 percent more than the free. On the eve of the Civil War, slavery flourished in the South and generated a rate of economic growth comparable to that of many European countries, according to Fogel and Engerman. They also discovered that, because slaves constituted a considerable portion of individual wealth, masters fed and treated their slaves reasonably well. Although some evidence indicates that infant and young slaves suffered much worse conditions than their freeborn counterparts, teenaged and adult slaves lived in conditions similar to — sometimes better than — those enjoyed by many free laborers of the same period.

Transition from Indentured Servitude to Slavery

One potent piece of evidence supporting the notion that slavery provides pecuniary benefits is this: slavery replaces other labor when it becomes relatively cheaper. In the early U.S. colonies, for example, indentured servitude was common. As the demand for skilled servants (and therefore their wages) rose in England, the cost of indentured servants went up in the colonies. At the same time, second-generation slaves became more productive than their forebears because they spoke English and did not have to adjust to life in a strange new world. Consequently, the balance of labor shifted away from indentured servitude and toward slavery.

Gang System

The value of slaves arose in part from the value of labor generally in the antebellum U.S. Scarce factors of production command economic rent, and labor was by far the scarcest available input in America. Moreover, a large proportion of the reward to owning and working slaves resulted from innovative labor practices. Certainly, the use of the “gang” system in agriculture contributed to profits in the antebellum period. In the gang system, groups of slaves perfomed synchronized tasks under the watchful overseer’s eye, much like parts of a single machine. Masters found that treating people like machinery paid off handsomely.

Antebellum slaveowners experimented with a variety of other methods to increase productivity. They developed an elaborate system of “hand ratings” in order to improve the match between the slave worker and the job. Hand ratings categorized slaves by age and sex and rated their productivity relative to that of a prime male field hand. Masters also capitalized on the native intelligence of slaves by using them as agents to receive goods, keep books, and the like.

Use of Positive Incentives

Masters offered positive incentives to make slaves work more efficiently. Slaves often had Sundays off. Slaves could sometimes earn bonuses in cash or in kind, or quit early if they finished tasks quickly. Some masters allowed slaves to keep part of the harvest or to work their own small plots. In places, slaves could even sell their own crops. To prevent stealing, however, many masters limited the products that slaves could raise and sell, confining them to corn or brown cotton, for example. In antebellum Louisiana, slaves even had under their control a sum of money called a peculium. This served as a sort of working capital, enabling slaves to establish thriving businesses that often benefited their masters as well. Yet these practices may have helped lead to the downfall of slavery, for they gave slaves a taste of freedom that left them longing for more.

Slave Families

Masters profited from reproduction as well as production. Southern planters encouraged slaves to have large families because U.S. slaves lived long enough — unlike those elsewhere in the New World — to generate more revenue than cost over their lifetimes. But researchers have found little evidence of slave breeding; instead, masters encouraged slaves to live in nuclear or extended families for stability. Lest one think sentimentality triumphed on the Southern plantation, one need only recall the willingness of most masters to sell if the bottom line was attractive enough.

Profitability and African Heritage

One element that contributed to the profitability of New World slavery was the African heritage of slaves. Africans, more than indigenous Americans, were accustomed to the discipline of agricultural practices and knew metalworking. Some scholars surmise that Africans, relative to Europeans, could better withstand tropical diseases and, unlike Native Americans, also had some exposure to the European disease pool.

Ease of Identifying Slaves

Perhaps the most distinctive feature of Africans, however, was their skin color. Because they looked different from their masters, their movements were easy to monitor. Denying slaves education, property ownership, contractual rights, and other things enjoyed by those in power was simple: one needed only to look at people to ascertain their likely status. Using color was a low-cost way of distinguishing slaves from free persons. For this reason, the colonial practices that freed slaves who converted to Christianity quickly faded away. Deciphering true religious beliefs is far more difficult than establishing skin color. Other slave societies have used distinguishing marks like brands or long hair to denote slaves, yet color is far more immutable and therefore better as a cheap way of keeping slaves separate. Skin color, of course, can also serve as a racist identifying mark even after slavery itself disappears.

Profit Estimates

Slavery never generated superprofits, because people always had the option of putting their money elsewhere. Nevertheless, investment in slaves offered a rate of return — about 10 percent — that was comparable to returns on other assets. Slaveowners were not the only ones to reap rewards, however. So too did cotton consumers who enjoyed low prices and Northern entrepreneurs who helped finance plantation operations.

Exploitation Estimates

So slavery was profitable; was it an efficient way of organizing the workforce? On this question, considerable controversy remains. Slavery might well have profited masters, but only because they exploited their chattel. What is more, slavery could have locked people into a method of production and way of life that might later have proven burdensome.

Fogel and Engerman (1974) claimed that slaves kept about ninety percent of what they produced. Because these scholars also found that agricultural slavery produced relatively more output for a given set of inputs, they argued that slaves may actually have shared in the overall material benefits resulting from the gang system. Other scholars contend that slaves in fact kept less than half of what they produced and that slavery, while profitable, certainly was not efficient. On the whole, current estimates suggest that the typical slave received only about fifty percent of the extra output that he or she produced.

Did Slavery Retard Southern Economic Development?

Gavin Wright (1978) called attention as well to the difference between the short run and the long run. He noted that slaves accounted for a very large proportion of most masters’ portfolios of assets. Although slavery might have seemed an efficient means of production at a point in time, it tied masters to a certain system of labor which might not have adapted quickly to changed economic circumstances. This argument has some merit. Although the South’s growth rate compared favorably with that of the North in the antebellum period, a considerable portion of wealth was held in the hands of planters. Consequently, commercial and service industries lagged in the South. The region also had far less rail transportation than the North. Yet many plantations used the most advanced technologies of the day, and certain innovative commercial and insurance practices appeared first in transactions involving slaves. What is more, although the South fell behind the North and Great Britain in its level of manufacturing, it compared favorably to other advanced countries of the time. In sum, no clear consensus emerges as to whether the antebellum South created a standard of living comparable to that of the North or, if it did, whether it could have sustained it.

Ultimately, the South’s system of law, politics, business, and social customs strengthened the shackles of slavery and reinforced racial stereotyping. As such, it was undeniably evil. Yet, because slaves constituted valuable property, their masters had ample incentives to take care of them. And, by protecting the property rights of masters, slave law necessarily sheltered the persons embodied within. In a sense, the apologists for slavery were right: slaves sometimes fared better than free persons because powerful people had a stake in their well-being.

Conclusion: Slavery Cannot Be Seen As Benign

But slavery cannot be thought of as benign. In terms of material conditions, diet, and treatment, Southern slaves may have fared as well in many ways as the poorest class of free citizens. Yet the root of slavery is coercion. By its very nature, slavery involves involuntary transactions. Slaves are property, whereas free laborers are persons who make choices (at times constrained, of course) about the sort of work they do and the number of hours they work.

The behavior of former slaves after abolition clearly reveals that they cared strongly about the manner of their work and valued their non-work time more highly than masters did. Even the most benevolent former masters in the U.S. South found it impossible to entice their former chattels back into gang work, even with large wage premiums. Nor could they persuade women back into the labor force: many female ex-slaves simply chose to stay at home. In the end, perhaps slavery is an economic phenomenon only because slave societies fail to account for the incalculable costs borne by the slaves themselves.


For studies pertaining to the economics of slavery, see particularly Aitken, Hugh, editor. Did Slavery Pay? Readings in the Economics of Black Slavery in the United States. Boston: Houghton-Mifflin, 1971.

Barzel, Yoram. “An Economic Analysis of Slavery.” Journal of Law and Economics 20 (1977): 87-110.

Conrad, Alfred H., and John R. Meyer. The Economics of Slavery and Other Studies. Chicago: Aldine, 1964.

David, Paul A., Herbert G. Gutman, Richard Sutch, Peter Temin, and Gavin Wright. Reckoning with Slavery: A Critical Study in the Quantitative History of American Negro Slavery. New York: Oxford University Press, 1976

Fogel , Robert W. Without Consent or Contract. New York: Norton, 1989.

Fogel, Robert W., and Stanley L. Engerman. Time on the Cross: The Economics of American Negro Slavery. New York: Little, Brown, 1974.

Galenson, David W. Traders, Planters, and Slaves: Market Behavior in Early English America. New York: Cambridge University Press, 1986

Kotlikoff, Laurence. “The Structure of Slave Prices in New Orleans, 1804-1862.” Economic Inquiry 17 (1979): 496-518.

Ransom, Roger L., and Richard Sutch. One Kind of Freedom: The Economic Consequences of Emancipation. New York: Cambridge University Press, 1977.

Ransom, Roger L., and Richard Sutch “Capitalists Without Capital” Agricultural History 62 (1988): 133-160.

Vedder, Richard K. “The Slave Exploitation (Expropriation) Rate.” Explorations in Economic History 12 (1975): 453-57.

Wright, Gavin. The Political Economy of the Cotton South: Households, Markets, and Wealth in the Nineteenth Century. New York: Norton, 1978.

Yasuba, Yasukichi. “The Profitability and Viability of Slavery in the U.S.” Economic Studies Quarterly 12 (1961): 60-67.

For accounts of slave trading and sales, see
Bancroft, Frederic. Slave Trading in the Old South. New York: Ungar, 1931. Tadman, Michael. Speculators and Slaves. Madison: University of Wisconsin Press, 1989.

For discussion of the profession of slave catchers, see
Campbell, Stanley W. The Slave Catchers. Chapel Hill: University of North Carolina Press, 1968.

To read about slaves in industry and urban areas, see
Dew, Charles B. Slavery in the Antebellum Southern Industries. Bethesda: University Publications of America, 1991.

Goldin, Claudia D. Urban Slavery in the American South, 1820-1860: A Quantitative History. Chicago: University of Chicago Press,1976.

Starobin, Robert. Industrial Slavery in the Old South. New York: Oxford University Press, 1970.

For discussions of masters and overseers, see
Oakes, James. The Ruling Race: A History of American Slaveholders. New York: Knopf, 1982.

Roark, James L. Masters Without Slaves. New York: Norton, 1977.

Scarborough, William K. The Overseer: Plantation Management in the Old South. Baton Rouge, Louisiana State University Press, 1966.

On indentured servitude, see
Galenson, David. “Rise and Fall of Indentured Servitude in the Americas: An Economic Analysis.” Journal of Economic History 44 (1984): 1-26.

Galenson, David. White Servitude in Colonial America: An Economic Analysis. New York: Cambridge University Press, 1981.

Grubb, Farley. “Immigrant Servant Labor: Their Occupational and Geographic Distribution in the Late Eighteenth Century Mid-Atlantic Economy.” Social Science History 9 (1985): 249-75.

Menard, Russell R. “From Servants to Slaves: The Transformation of the Chesapeake Labor System.” Southern Studies 16 (1977): 355-90.

On slave law, see
Fede, Andrew. “Legal Protection for Slave Buyers in the U.S. South.” American Journal of Legal History 31 (1987). Finkelman, Paul. An Imperfect Union: Slavery, Federalism, and Comity. Chapel Hill: University of North Carolina, 1981.

Finkelman, Paul. Slavery, Race, and the American Legal System, 1700-1872. New York: Garland, 1988.

Finkelman, Paul, ed. Slavery and the Law. Madison: Madison House, 1997.

Flanigan, Daniel J. The Criminal Law of Slavery and Freedom, 1800-68. New York: Garland, 1987.

Morris, Thomas D., Southern Slavery and the Law: 1619-1860. Chapel Hill: University of North Carolina Press, 1996.

Schafer, Judith K. Slavery, The Civil Law, and the Supreme Court of Louisiana. Baton Rouge: Louisiana State University Press, 1994.

Tushnet, Mark V. The American Law of Slavery, 1810-60: Considerations of Humanity and Interest. Princeton: Princeton University Press, 1981.

Wahl, Jenny B. The Bondsman’s Burden: An Economic Analysis of the Common Law of Southern Slavery. New York: Cambridge University Press, 1998.

Other useful sources include
Berlin, Ira, and Philip D. Morgan, eds. The Slave’s Economy: Independent Production by Slaves in the Americas. London: Frank Cass, 1991.

Berlin, Ira, and Philip D. Morgan, eds, Cultivation and Culture: Labor and the Shaping of Slave Life in the Americas. Charlottesville, University Press of Virginia, 1993.

Elkins, Stanley M. Slavery: A Problem in American Institutional and Intellectual Life. Chicago: University of Chicago Press, 1976.

Engerman, Stanley, and Eugene Genovese. Race and Slavery in the Western Hemisphere: Quantitative Studies. Princeton: Princeton University Press, 1975.

Fehrenbacher, Don. Slavery, Law, and Politics. New York: Oxford University Press, 1981.

Franklin, John H. From Slavery to Freedom. New York: Knopf, 1988.

Genovese, Eugene D. Roll, Jordan, Roll. New York: Pantheon, 1974.

Genovese, Eugene D. The Political Economy of Slavery: Studies in the Economy and Society of the Slave South . Middletown, CT: Wesleyan, 1989.

Hindus, Michael S. Prison and Plantation. Chapel Hill: University of North Carolina Press, 1980.

Margo, Robert, and Richard Steckel. “The Heights of American Slaves: New Evidence on Slave Nutrition and Health.” Social Science History 6 (1982): 516-538.

Phillips, Ulrich B. American Negro Slavery: A Survey of the Supply, Employment and Control of Negro Labor as Determined by the Plantation Regime. New York: Appleton, 1918.

Stampp, Kenneth M. The Peculiar Institution: Slavery in the Antebellum South. New York: Knopf, 1956.

Steckel, Richard. “Birth Weights and Infant Mortality Among American Slaves.” Explorations in Economic History 23 (1986): 173-98.

Walton, Gary, and Hugh Rockoff. History of the American Economy. Orlando: Harcourt Brace, 1994, chapter 13.

Whaples, Robert. “Where Is There Consensus among American Economic Historians?” Journal of Economic History 55 (1995): 139-154.

Data can be found at
U.S. Bureau of the Census, Historical Statistics of the United States, 1970, collected in ICPSR study number 0003, “Historical Demographic, Economic and Social Data: The United States, 1790-1970,” located at

Citation: Wahl, Jenny. “Slavery in the United States”. EH.Net Encyclopedia, edited by Robert Whaples. March 26, 2008. URL