Tommy Burns was a Canadian professional boxer. He remains the only Canadian-born fighter to win the World Heavyweight Championship and is the shortest champion in the division's history. Starting out at welterweight, he is the lightest boxer to eventually become heavyweight champion, and he is one of only two heavyweight champions to have fought below middleweight; the other boxer to do so was Roy Jones Jr., who began at light middleweight. The first to travel the globe in defending his title, Burns made 13 title defences against 11 different boxers, despite often being smaller than his opponents. World heavyweight champion (World) from February 23, 1906 to December 26, 1908. Wiki link