His first major international competition was at an Italian gymnastics festival in 1895, and then just a year later he found himself selected for the German team that travelled to Athens.
Together with his cousin Gustav, Flatow helped Germany win both team events, and he also won the individual parallel bars, and was the runner-up in the horizontal bar, taking his haul to the modern equivalent of three golds and a silver.
A co-founder of the Jewish Gymnastics Club, in 1933, Flatow was forced to end his gymnastics club membership. As a former Olympic champion, he was still honoured at the 1936 Olympics, but two years later, he fled to the Netherlands. However when the Nazis invaded Holland he was jailed and deported, ending his days, in 1942, in a concentration camp.
Since 1987, the German Gymnastics Federation awards the Flatow Medal, remembering both Alfred and Gustav, to be awarded for excellent all-around performances. And in 1997, the city of Berlin honoured Alfred and Gustav Flatow by renaming a street near the Olympic Stadium as Flatowallee (Flatow Way).