Billy Papke (born William Papke, and known as "The Illinois Thunderbolt") (September 17, 1886 – November 26, 1936) was an American boxer who held the World Middleweight Championship from September 7 to November 26, 1908.
In 1910-12, he also took the Australian and British versions of the World Middleweight Championship, though American boxing historians generally take less note of these titles.
With a solid and efficient punch, 70 percent of his better publicized career wins by decision were from knockouts, and roughly 40% of his reported fights were as well.