A few more things I can add about Jack Johnson:

His father, Henry, had been a slave in Texas, and the family was poor. Jack was the second of six children, and didn't have much schooling; he left after the fifth grade. He worked at odd jobs around South Texas, building his strength through throwing hay bales for white farmers; he also found employment as a dockworker, porter, and barber's helper. He first began boxing as a sparring partner; he fought in "battles royal", which saw young black men box to entertain white spectators who threw money to the winner; he then boxed in private clubs. He turned professional in 1897, but boxing was illegal in Texas, and he spent his first time in jail in 1901 when arrested for partaking in this criminal activity. He soon left Galveston for good.

Johnson, also known as the Galveston Giant - he was over six feet tall - defeated then champion Tommy Burns in Australia in 1908, which technically made him heavyweight champion. However, he wasn't officially recognized until the fight with Jim Jeffries in Las Vegas in 1910; Jeffries had refused to fight Johnson when he had been champ (1899-1904), and had come out of retirement to become the first great white hope who whites wished would defeat this big black boxer. He didn't, though; Johnson won. After the fight there were race riots in which hundreds of blacks and whites were injured and several died; films of Johnson's victories were subsequently banned in Texas for fear that they would incite more rioting. Black poet William Waring Cuney gave a rather different view of Johnson's victory than was held by most whites in his poem "My Lord, What a Morning":

O my Lord
What a morning,
O my Lord,
What a feeling,
When Jack Johnson
Turned Jim Jeffries'
Snow-white face
to the ceiling.

Johnson raised the ire of whites in another way: they resented the fact that he liked the good life. He had his own jazz band, owned a Chicago nightclub, drove flashy yellow sports cars, and was said to walk his pet leopard while sipping champagne. He had gold teeth and a gold-handled walking stick and boasted of his conquests of whites - white men in the ring, white women out of it. Johnson was romantically linked with Moulin Rouge star Mistinguette, German spy Mata Hari, and sex symbols Lupe Velez and Mae West. He married three times: Etta Terry Duryea in 1911 (she committed suicide the next year); Lucille Cameron in 1913 (they divorced in 1924); and Irene Marie Pineau in 1925. All these women were white. In spite of all that marrying and carrying on, though, he never had any children.

Here's an odd factoid: Jack Johnson invented and patented a wrench in 1922. Hard to connect this to the rest of his life. There's a picture of it at inventors.about.com/library/inventors/blwrench1.htm.

Despite the fact that Johnson is Galveston's most famous athlete, he hasn't been much celebrated there. In the 1980s the city erected a black-metal, modernistic sculpture in a park to honour Johnson, but after it became the target of racist attacks and salt air, it was removed.