On Oct. 16, 1968, American sprinters Tommie Smith and John Carlos stood on the medal stand after the men's 200-meter race at the Mexico City Olympics and each raised a black-gloved fist as the U.S. national anthem played, HISTORY and the BBC reported.

Smith had won gold, setting a world record, and Carlos took bronze, the BBC said. The two wore black socks with no shoes to represent Black poverty, and Carlos wore beads to protest lynching, the outlets reported.

HISTORY reported that the two shared one pair of black gloves, so Smith raised his right hand and Carlos his left. The BBC said Smith's raised right fist stood for Black Power and Carlos's left fist for Black unity.

Australian silver medalist Peter Norman wore a pin for the Olympic Project for Human Rights in support, HISTORY said. The group, led by San Jose State sociologist Harry Edwards, used sports to call attention to how Black athletes were treated, HISTORY reported.

The protest came months after the assassinations of the Rev. Martin Luther King Jr. and Robert Kennedy, the BBC noted.

The reaction was swift. Within hours, the International Olympic Committee condemned them, and two days later they were suspended from the U.S. team and sent home, the BBC reported. HISTORY said they were booed and attacked in the American press.

Smith later faced death threats, and by 1972 the world's fastest man was training schoolchildren in Wakefield, England, to make a living, the BBC reported.

Years later, the protest became a symbol of the civil rights movement. In 2008, the two men received the Arthur Ashe Courage Award, the BBC said. "We had to be seen because we couldn't be heard," Smith later said of the protest, according to HISTORY.

What we know: Smith and Carlos raised their fists on the Mexico City medal stand on Oct. 16, 1968.
What we don't: How many people saw the moment live on television.