The 1964 Summer Olympics, officially the Games of the XVIII Olympiad and commonly known as Tokyo 1964, were an international multi-sport event held from 10 to 24 October 1964 in Tokyo, Japan. Tokyo had been awarded the organization of the 1940 Summer Olympics, but this honor was subsequently passed to Helsinki due to Japan's invasion of China, before ultimately being cancelled due to World War II. The 1964 Summer Olympics in Tokyo were the first Olympic Games held in the city and, as of 2021, the only ones to have spectators, as the 2020 Summer Olympics in Tokyo were conducted without spectators due to the COVID-19 pandemic. Tokyo was chosen as the host city during the 55th IOC Session in West Germany on 26 May 1959.
The 1964 Summer Games were the first Olympics held in Asia, and marked the first time South Africa was excluded for using its apartheid system in sports. Until 1960, South Africa had fielded segregated teams, conforming to the country's racial classifications; for the 1964 Games the International Olympic Committee demanded a multi-racial delegation to be sent, and after South Africa refused, they were excluded from participating. The country was, however, allowed to compete at the 1964 Summer Paralympics, also held in Tokyo, its Paralympic Games debut.