Thomas Jefferson’s writings on American grievances justifying the Revolution, he attacked the British for sponsoring the slave trade to the colonies.
- In 1778, with his leadership, slave importation was banned in Virginia, one of the first jurisdictions worldwide to do so.
- Jefferson was a lifelong advocate of ending the trade and as president led the effort to criminalize the international slave trade that passed Congress and he signed in 1808, a year after the British did the same thing.
- In 1779, as a practical solution to end slavery, Jefferson supported gradual emancipation, training, and colonization of African-American slaves rather than unconditional manumission, believing that releasing unprepared slaves with no place to go and no means to support themselves would only bring them misfortune.
- In 1784, Jefferson proposed federal legislation banning slavery in the New Territories of the North and South after 1800, which failed to pass Congress by one vote.