The 1968 Summer Olympics, officially known as the Games of the XIX Olympiad, were an international multi-sport event held in Mexico City in October 1968. The 1968 Games were preceded by the Tlatelolco massacre, in which hundreds of students were killed by security forces ten days before the opening day. It is the only Games ever held in Latin America, and it was the second to be hosted outside of Europe, Australia, or the United States.

On October 2, 1968, ten days before the start of the 1968 Summer Olympics the Plaza de las Tres Culturas was the scene of the Tlatelolco massacre, in which more than 300 student protesters were killed by army and police. After the event, the International Olympic Committee held an urgent meeting to consider cancelling the games.

On October 16, 1968, an action by two African-American sprinters at the Mexico City Olympics shook the sporting world. Tommie Smith and John Carlos, the gold and bronze medalists in the men's 200-meter race, took their places on the podium for the medal ceremony barefooted and wearing civil rights badges, lowered their heads and each defiantly raised a black-gloved fist as the Star Spangled Banner was played. Both of them were members of the Olympic Project for Human Rights.

Some people (particularly IOC president Avery Brundage) felt that a political statement had no place in the international forum of the Olympic Games. In an immediate response to their actions, Smith and Carlos were suspended from the U.S. team by Brundage and banned from the Olympic Village. Those who opposed the protest said the actions disgraced all Americans. Supporters, on the other hand, praised the men for their bravery.

Peter Norman, the Australian sprinter who came second in the 200 m race, and Martin Jellinghaus, a member of the German bronze medal-winning 1600-meter relay team, also wore Olympic Project for Human Rights badges at the games to show support for the suspended American sprinters.

In another incident, while standing on the medal podium after the balance beam event final, Czechoslovakian gymnast Věra Čáslavská quietly turned her head down and away during the playing of the Soviet national anthem. The action was Čáslavská's silent protest against the recent Soviet invasion of Czechoslovakia, and was repeated when she accepted her medal for her floor exercise routine. While Čáslavská's countrymen supported her actions and her outspoken opposition to Communism (she had publicly signed and supported Ludvik Vaculik's "Two Thousand Words" manifesto), the new regime responded by banning her from both sporting events and international travel for many years.