At the time of the American founding, there were about half a million slaves in the United States, mostly in the five southernmost states, where they made up 40% of the population. Many of the leading American founders – most notably Thomas Jefferson, George Washington, and James Madison – owned slaves, but many others did not. Benjamin Franklin thought that slavery was "an atrocious debasement of human nature" and "a source of serious evils." He and Benjamin Rush founded the Pennsylvania Society for Promoting the Abolition of Slavery in 1774. In 1790, Quakers from New York and Pennsylvania presented their petition for abolition to Congress. Their argument against slavery was backed by the Pennsylvania Abolitionist Society.

In his later years, as Congress was forced to deal with the issue of slavery, Franklin wrote several essays that stressed the importance of the abolition of slavery and of the integration of African Americans into American society. These writings included:

• An Address to the Public (1789)
• A Plan for Improving the Condition of the Free Blacks (1789)
• Sidi Mehemet Ibrahim on the Slave Trade (1790)