The term "Uncle Tom" is based upon the main character in Harriet Beecher Stowe's novel 'Uncle Tom's Cabin.' Stowe's novel is about a Black man named Tom who jumps from a paddle wheeler to rescue the daughter of a rich white man. As a reward for saving his daughter, the white man purchases him at a slave auction, and allows Tom to live with him and his daughter as her Uncle Tom.
The white man's son betrays his father's will to free Tom when he died. He instead sells him to the infamous Simon Legree, who eventually murders Tom for disobeying his order to beat some of his fellow enslaved people.