Slavery in the United States Slavery in the United States Slavery in the United States was the legal institution of human chattel enslavement, primarily of Africans and African Americans, that existed in the United States of America in the 18th and 19th centuries. Slavery had been practiced in British America from early colonial days, and was legal in all Thirteen Colonies at the time of the Declaration of Independence in 1776. It lasted in about half the states until 1865, when it was prohibited nationally by the Thirteenth Amendment. As an economic system, slavery was largely replaced by sharecropping. By the time of the American
United States Declaration of Independence a means to present a distinctly American political identity, thereby stimulating public debate on a topic that few had previously dared to openly discuss, and public support for separation from Great Britain steadily increased after its publication. Some colonists still held out hope for reconciliation, but developments in early 1776 further strengthened public support for independence. In February 1776, colonists learned of Parliament's passage of the Prohibitory Act, which established a blockade of American ports and declared American ships to be enemy vessels. John Adams, a strong supporter of independence, believed that Parliament had effectively declared American independence before Congress