April 5 - 1915 - Jess Willard Defeats Jack Johnson for the World Heavyweight Championship
Jack Johnson would be a controversial figure today, as he was arrogant and lived a rather extravagant lifestyle. But as the first black heavyweight champion, in the first decades of the twentieth century, he was loathed by much of America. Additionally, he dated and married a series of white women, which made federal authorities charge him with violating the Mann Act. So he was the Heavyweight Champion, a fugitive from the law traveling around the world, and one of the most famous celebrities in the world. Eventually, the desire for a "Great White Hope" would land on Jess Willard, a giant Kansan, who would eventually defeat Jack Johnson in Havana, Cuba.

Which is What Happened Today, April 5, in 1915.