After World War II olympics

The first post-war Games were held in 1948 in London, with both Germany and Japan excluded. Dutch sprinter Fanny Blankers-Koen won four gold medals on the track, emulating Owens' achievement in Berlin.

At the 1952 Games in Helsinki the USSR team competed for the first time and immediately became one of the dominant teams. Finland made a legend of an amiable Czechoslovak army lieutenant named Emil Zátopek, who was intent on improving on his single gold and silver medals from 1948. Having first won both the 10,000 and 5,000 meter races, he also entered the marathon, despite having never previously raced at that distance. Pacing himself by chatting with the other leaders, Zátopek led from about half way, slowly dropping the remaining contenders to win by two and a half minutes, and completed a trio of wins.

The advent of the state-sponsored "full-time amateur athlete" of the Eastern Bloc countries further eroded the ideology of the pure amateur, as it put the self-financed amateurs of the Western countries at a disadvantage. The Soviet Union entered teams of athletes who were all nominally students, soldiers, or working in a profession, but many of whom were in reality paid by the state to train on a full-time basis.[11] Nevertheless, the IOC held to the traditional rules regarding amateurism.[12]

The 1956 Melbourne Games were largely successful, barring a water polo match between Hungary and the Soviet Union, which political tensions caused to end as a pitched battle between the teams. Due to a foot-and-mouth disease outbreak in Britain at the time and the strict quarantine laws of Australia, the equestrian events were held in Stockholm.

At the 1960 Rome Games a young light-heavyweight boxer named Cassius Clay, later known as Muhammad Ali, arrived on the scene. Ali would later throw his gold medal away in disgust after being refused service in a whites-only restaurant in his home town of Louisville, Kentucky.[13] Soviet women's artistic gymnastics team members won 15 of 16 possible medals. Other performers of note in 1960 included Wilma Rudolph, a gold medalist in the 100 meters, 200 meters and 4 × 100 meters relay events.

The 1964 Games held in Tokyo are notable for heralding the modern age of telecommunications. These games were the first to be broadcast worldwide on television, enabled by the recent advent of communication satellites. The 1964 Games were thus a turning point in the global visibility and popularity of the Olympics. Judo debuted as an official sport, and Dutch judoka Anton Geesink created quite a stir when he won the final of the open weight division, defeating Akio Kaminaga in front of his home crowd.

Performances at the 1968 Mexico City games were affected by the altitude of the host city,[14] specifically the long jump, in which American athlete Bob Beamon jumped 8.90 meters. Beamon's world record would stand for 23 years. The 1968 Games also introduced the now-universal Fosbury flop, a technique which won American high jumper Dick Fosbury the gold medal. Politics took center stage in the medal ceremony for the men's 200 meter dash, where Tommie Smith and John Carlos made a protest gesture on the podium against the segregation in the United States; their political act was condemned within the Olympic Movement, but was praised in the Black Power movement.

Politics again intervened at Munich in 1972, with lethal consequences. A Palestinian terrorist group named Black September invaded the Olympic village and broke into the apartment of the Israeli delegation. They killed two Israelis and held 9 others as hostages. The terrorists demanded that Israel release numerous prisoners. When the Israeli government refused their demand, a tense stand-off ensued while negotiations continued. Eventually the captors, still holding their hostages, were offered safe passage and taken to an airport, where they were ambushed by German security forces. In the firefight that followed, 15 people, including the nine Israeli athletes and five of the terrorists, were killed. After much debate, it was decided that the Games would continue, but proceedings were obviously dominated by these events.[15] Some memorable athletic achievements did occur during these Games, notably the winning of a then-record seven gold medals by United States swimmer Mark Spitz, Lasse Virén (of Finland)'s back-to-back gold in the 5,000 meters and 10,000 meters (defeating American distance running great Steve Prefontaine in the former), and the winning of three gold medals by 16-year-old Soviet gymnastic sensation Olga Korbut - who thrilled the world with an historic backflip off the high bar. Korbut, however, failed to win the all-around, losing to her teammate Ludmilla Tourischeva.

There was no such tragedy in Montreal in 1976, but bad planning and fraud led to the Games' cost far exceeding the budget. The Montreal Games were the most expensive in Olympic history, until the 2014 Winter Olympics, costing over $5 billion (equivalent to $20 billion in 2016). For a time, it seemed that the Olympics might no longer be a viable financial proposition. In retrospect, the belief that contractors (suspected of being members of the Montreal Mafia) skimmed large sums of money from all levels of contracts while also profiting from the substitution of cheaper building materials of lesser quality, may have contributed to the delays, poor construction and excessive costs. In 1988, one such contractor, Giuseppe Zappia "was cleared of fraud charges that resulted from his work on Olympic facilities after two key witnesses died before testifying at his trial."[16] There was also a boycott by African nations to protest against a recent tour of apartheid-run South Africa by the New Zealand national rugby union team. The Romanian gymnast Nadia Comăneci won the women's individual all around gold medal with two of four possible perfect scores, thus giving birth to a gymnastics dynasty in Romania. Another female gymnast to earn the perfect score and three gold medals there was Nellie Kim of the USSR. Lasse Virén repeated his double gold in the 5,000 meters and 10,000 meters, making him the first athlete to ever win the distance double twice.