Born in Toronto, Canada on February 12, 1889, Johnny Coulon spent most of his life in Chicago. He became a professional boxer in 1905, and in 1910, he defeated Jim Kendrick to clench the world bantamweight title. He successively defended the title for 3 years until losing to Kid Williams in 1914.
During World War I, Coulon fought in the Army, imparting much of his fighting knowledge to other soldiers. In 1920, Coulon retired from boxing in 1920. He opened up a gym in Chicago with his wife, and he passed away in 1973.