1910s: Sam Langford — Small man beat the best big men of his day. Runner up: Jimmy Wilde.

1920s: Benny Leonard — Some still say he’s the greatest lightweight ever. Runner up: Harry Greb.

1930s: Henry Armstrong — Held titles in three weight classes simultaneously. Runner up: Tony Canzoneri.

1940s: Ray Robinson – Untouchable as a welterweight. Runner up: Willie Pep

1950s: Ray Robinson – Also one of the greatest middleweights ever. Runner up: Archie Moore.

1960s: Muhammad Ali – The Greatest really was the greatest at this time. Runner up: Carlos Ortiz.

1970s: Roberto Duran – Virtually untouchable as a lightweight. Runner up: Carlos Monzon.

1980s: Ray Leonard: His victories over Duran, Hearns and Hagler were epic. Runner up: Julio Cesar Chavez.

1990s: Roy Jones Jr. – At his best, he inspired awe. Runner up: Pernell Whitaker.

2000s: Manny Pacquiao – Sorry Floyd but you need to fight the best to be the best. Runner up: Floyd Mayweather.

(via The Ring)