Thil won the French middleweight boxing championship in 1928 and captured the Europe title the following year. After losing his European championship in 1930, Thil won his next 15 fights and then defeated Gorilla Jones by a controversial 11th-round disqualification to capture the National Boxing Association (NBA) world middleweight championship and the vacant International Boxing Union (IBU) world middleweight championship on June 11, 1932, in Paris, France. With his championship victory, Thil became the toast of Paris. He was a major celebrity and a good friend of celebrated actor Jean Gabin.