Irish-born John Flanagan was already the world record holder for the hammer throw when he emigrated to the United States in 1897. He became a policeman in New York City and represented the US in international sporting events. At the 1900 Paris Olympics, Flanagan won the hammer throw easily, outdistancing fellow American Truxton Hare by 4.75m.
Four years later, at the St. Louis Olympics, in an competition devoid of foreign entries, Flanagan successfully defended his title, although he was given a good test by John DeWitt, and won by less than a metre. A week later, Flanagan picked up a silver medal in the 56-pound (25.4-kg) weight throw.
At the 1908 London Games, Flanagan overcame world record holder Matt McGrath with his last attempt to win his third straight hammer throw gold medal. He also competed in the tug-of-war. On 24 July 1909, Flanagan threw the hammer 56.18m to become the oldest world record breaker in the history of athletics. He was 41 years, 196 days old. Flanagan returned to Ireland in 1911 and lived there until his death in 1938.