First published in 1927, Jack Johnson's autobiography, Jack Johnson: In the Ring and Out, remains the key source for information about his life. As he himself states in it: "I am astounded when I realize that there are few men in any period of the world's history, who have led a more varied or intense existence than I [have]."

Jack Johnson, who became the first black heavyweight boxing champion in the world in 1908, was the preeminent American sports personality of his era, a man whose success in the ring spurred a worldwide search, tinged with bigotry, for a "Great White Hope" to defeat him. Handsome, successful, and personable, Johnson was known as much for his exploits outside of the ring as for his boxing skills. He married three white women in a time when such interracial unions resulted in denunciations of him from the floor of the United States Congress. He made big money, spent it lavishly, and lived grandly. And in doing so he gained admirers and detractors all over the world and became, quite simply, one of the best known men of the early twentieth century.