Tommie Smith and John Carlos - Mexico 1968
At a time of heightened racial tensions in America, Smith and Carlos, rather than face the United States flag, bowed their heads and raised gloved fists in protest at racism in their home country during the medal ceremony for the 200 metres.
The incident caused outrage with both athletes being banned from the Olympic village.
However, as with many protests of this kind, passage of time showed it to be a milestone in America's civil rights movement and both men received honours in 1998, on the 30th anniversary of their protest.
