Tyson Fury
Having been told be could not fight for Ireland at the Olympic Games, he was allowed to fight for both Great Britain and Ireland after tracing his family back to relatives in Belfast and Galway. Fury has fought for both England and Ireland as an amateur, winning the ABA super-heavyweight title in 2008 before turning professional later that year. He has since held the British and English heavyweight titles twice each, as well as the European, Commonwealth, and Irish heavyweight titles.