When the founding fathers assembled at the Constitutional Convention in 1787, slavery was firmly established in the five southernmost states. But as Stanford University historian Don E. Fehrenbacher notes,

Slavery was an institution under severe scrutiny, both as a matter of conscience and as a matter of public interest. Many Americans were finding it difficult to square slaveholding with the principles of Christianity, and many were troubled by the contrast between the celebration of human freedom in the Declaration of Independence and the presence of human servitude throughout so much of the Republic.

Despite these concerns, in the nation’s first decades slavery was only abolished where it was unprofitable. And as Harvard historian Nathan Irving Huggins writes, “The Founding Fathers . . . did not address frankly and openly, in any of their official documents, the conspicuous fact of racial slavery.” The U...