Billy Conn was an American boxer of Irish descent who began as a lightweight and worked his way up to heavyweight. Conn was light heavyweight world champion from 1939 to 1940, after which he entered competition as a heavyweight.

On 18 June 1941, he faced off against world heavyweight champion Joe Louis at the Polo Grounds in New York, Conn’s most famous fight. He led on points at the start of the thirteenth round, but was overconfident and lost the match by KO. Conn fought Louis once again on 19 June 1946, but emerged as the clear loser after getting knocked out in the eighth round.

Conn had a boxing record of 63 wins in 75 fights, with 11 losses and 1 draw.

Conn was inducted into the International Boxing Hall of Fame in 1990.