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1800s-1850s: Expansion of slavery in the U.S.

History: Race in the U.S.A., a timeline created by the American Anthropological Association, looks at milestones in thinking and actions about race in government, science and society.
Image: 1854 map
This 1854 map shows slave states (grey), free states (red), and U.S. territories (green) with Kansas at the center. The map represents the territorial compromise of the Kansas–Nebraska Act. A federal law passed on May 30, 1854, the act provided the framework for organizing territorial governments for what would later became the states of Kansas and Nebraska and provided that each territory would decide whether to allow slavery or not by popular vote, overturning the Missouri Compromise of 1820. Library of Congress / American Memories Collection
/ Source: American Anthropological Association

By the beginning of the 19th century, slavery in the U.S. was firmly established with a series of statutes and penal codes enacted in various states to regulate the activity of slaves and all conduct involving slaves and free blacks. With the Louisiana Purchase, the question of slavery became both geographical and political, and ushered in a period of national debate between pro- and anti-slavery states to gain political and economic advantage. But by 1820, Congress was embroiled in the debate over how to divide the newly acquired territories into slave and free states.

The Missouri Compromise—also referred to as the Compromise of 1820—was an agreement between the pro- and anti-slavery factions regulating slavery in the western territories. It prohibited slavery in new states north of the border of the Arkansas territory, excluding Missouri. Constitutionally, the Compromise of 1820 established a precedent for the exclusion of slavery from public territory acquired after the Constitution, and also recognized that Congress had no right to impose upon states seeking admission to the Union conditions that did not apply to those states already in the Union. After Missouri's admission to the Union in 1821, no other states were admitted until 1836 when Arkansas became a slave state, followed by Michigan in 1837 as a free state. Indeed, the debate over slave and free states remained relatively calm for almost 30 years. However by the late 1840s, several events occurred that upset the balance: the U.S. added new territory as a result of the Mexican war, and the question of whether that territory would be slave or free arose again. California, beneficiary of an increased population because of the gold rush—petitioned Congress to enter the Union as a free state. At the same time, Texas laid claim to territory extending all the way to Santa Fe. Of course Washington, D.C., the nation’s capital, not only allowed slavery but was home to the largest slave market in North America.

In January 1850, Henry Clay presented a bill that would become known as the Compromise of 1850. The terms of the bill included a provision that Texas relinquish its disputed land in exchange for $10 million to be paid to Mexico. The territories of New Mexico, Nevada, Arizona, and Utah were defined while leaving the question of slavery off the table, on the understanding that the issue would be decided when the territories applied for statehood. In addition, the slave trade would be abolished in the District of Columbia, although slavery would still be permitted in the nation’s capitol. It was agreed that California would be admitted as a free state, but the Fugitive Slave Act was passed to mollify pro-slavery states. This bill was the most controversial of all the bills that made up the Compromise of 1850. According to its tenets, citizens were required to aid in the recovery of fugitive slaves. Fugitives had no right to a jury trial. The cases were handled by special commissioners, who were paid $5 if a fugitive was released and $10 if the captive was returned to slavery. In addition, the act called for changes that made the process for filing a claim against a fugitive easier for slave owners. The new law was devastating. Many former slaves who had been attempting to build lives in the North left their homes and fled to Canada, which added approximately 20,000 blacks to its population over the following decade. Harriet Jacobs, a fugitive living in New York, described this period as “the beginning of a reign of terror to the colored population.” She was one of the runaways who remained in New York, despite learning that slave catchers had been hired to track her down. Many were captured and returned to slavery, however, including Anthony Burns, a fugitive living in Boston. Even free blacks, too, were captured and sent to the South, completely defenseless with no legal rights. The compromise lasted until the passage of the Kansas-Nebraska Act in 1854, when Illinois Senator Stephen Douglas proposed legislation allowing the issue of slavery to be decided in the new territories.

In 1801, Congress extended Virginia and Maryland slavery laws to the District of Columbia, establishing a federally sanctioned slave code.

In 1803, the Louisiana Purchase added Creoles and French settlers to the U.S. population. Congress approved the Louisiana Purchase from France for $15 million, which virtually doubled the country’s land size. It also re-ignited controversy over the spread of slavery in the territory.

In 1807, Congress banned the importation of slaves into the U.S., although smuggling continued in some parts of the South. Once the transatlantic slave trade was prohibited, domestic slave trading throughout the South increased.

The 1820 census added free colored persons to its racial categories.

In 1820, the Missouri Compromise brought Missouri and Maine into the Union. By this time more than 20,000 Indians lived in virtual slavery on California missions. The same year, Congress made trade in foreign slaves an act of piracy.

In 1821, Missouri entered the Union as the 24th state and a slave-holding state, maintaining the balance of slave and free states.

The Office of Indian Affairs was created in 1824.

In 1825, a ship operated by the U.S. Revenue seized a slave ship, the Antelope, sailing under a Venezuelan flag with a cargo of 281 Africans. The case was brought before the U.S. Supreme Court, which issued a unanimous opinion declaring the slave trade to be a violation of natural law. Only some of the Africans were set free, however, since the ruling also held that the U.S. could not prescribe law for other nations, and the slave trade was legal in Spain, Portugal and Venezuela. The 39 Africans designated by the court as property of Spain and the Antelope itself were restored to their owners.

The Compromise of 1850 admitted California as a free state; voters in New Mexico and Utah territories would decide whether they would be slave or free upon applying for statehood.

The new Fugitive Slave Act, also passed in 1850, made the federal government responsible for apprehending fugitive slaves in the North, and sending them back to the South. This extended slavery and its enforcement beyond the South. The South, however, felt that even this law was not strong enough, and the demand for more effective legislation resulted in enactment of a second Fugitive Slave Act that same year. However, the law was so severe that its implementation was open to abuses that defeated its purpose. Even during the Civil War, the Fugitive Slave Acts were used to prosecute blacks fleeing their masters in border states that were loyal to the Union. The acts were eventually repealed, but not until June of 1864.

In 1851 Shadrach Minkins, an African American working as a waiter in Boston, was abducted by slave catchers. Before he could be freed by legal means in a challenge to the Fugitive Slave law, Minkins was rescued by a group of African Americans.

In 1854, the Kansas-Nebraska Act passed, dividing the region along the 40th parallel, with Kansas to the south and Nebraska to the north, and providing both territories the right to vote on whether to be slave or free. For all practical purposes the act effectively repealed the Missouri Compromise and the Compromise of 1850, which had attempted to regulate the spread of slavery. As a result of the new law, both pro- and anti-slavery supporters tried to convince settlers to move to Kansas in order to sway the vote. The New England Emigrant Aid Company, an anti-slavery group, was very successful, and a group of anti-slavery activists was established around the town of Lawrence, Kansas. At the same time, pro-slavery settlers from Missouri began moving across the border to Kansas, some establishing themselves as residents of the territory, others simply coming across to vote. They were called “border ruffians” by their opponents. Lecompton, Kansas, the territorial capital, boiled with tension over the issue, and so-called “free-soilers” felt so threatened there that they set up their own unofficial legislature at Topeka. The enmity between the sides verged on civil war, and the period became known as "Bleeding Kansas."

The Dred Scott decision was handed down in 1857, which denied citizenship to free and enslaved blacks.