John Quincy Adams: Anti-Slavery Champion, His Lifetime of Public Service, Guided by the Bible - American Minute with Bill Federer
In Congress, he earned the nicknamed "The Hell-Hound of Slavery" for relentlessly speaking out against slavery.
He single-handedly led the fight to lift the Gag Rule which prohibited discussion of slavery on the House floor. As a result, Southern Democrats tried to have him censured in 1837.
In 1839, he introduced a constitutional amendment to ban slavery in all new states entering the Union.