() the Colonial era, Southern planters regularly purchased imported slaves, and merchants in New York and New England profited handsomely from the trade.
The American Revolution threw the slave trade and slavery itself into crisis. In the run-up to war, Congress banned the importation of slaves as part of a broader nonimportation policy. During the War of Independence, tens of thousands of slaves escaped to British lines. Many accompanied the British out of the country when peace arrived.
Inspired by the ideals of the Revolution, most of the newly independent American states banned the slave trade. But importation resumed to South Carolina and Georgia, which had been occupied by the British during the war and lost the largest number of slaves.
The slave trade was a major source of disagreement at the Constitutional Convention of 1787. South Carolina’s delegates were determined to protect slavery, and they had a powerful impact on the final document. They originated the three-fifths clause (giving the South extra representation in Congress by counting part of its slave population) and threatened disunion if the slave trade were banned, as other states demanded.
The result was a compromise barring Congress from prohibiting the importation of slaves until 1808. Some Anti-Federalists, as opponents of ratification were called, cited the slave trade clause as a reason why the Constitution should be rejected, claiming it brought shame upon the new nation....
As slavery expanded into the Deep South, a flourishing internal slave trade replaced importation from Africa. Between 1808 and 1860, the economies of older states like Virginia came increasingly to rely on the sale of slaves to the cotton fields of Alabama, Mississippi and Louisiana. But demand far outstripped supply, and the price of slaves rose inexorably, placing ownership outside the reach of poorer Southerners.〔
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