The 1948 Summer Olympics were an international multi-sport event held from 29 July to 14 August 1948 in London, United Kingdom. Following a twelve-year hiatus caused by the outbreak of World War II, these were the first Summer Olympics held since the 1936 Games in Berlin. The 1940 Olympic Games had been scheduled for Tokyo and then for Helsinki, while the 1944 Olympic Games had been provisionally planned for London. This was the second time London hosted the Olympic Games, having previously hosted them in 1908, forty years earlier. The Olympics would return again to London 64 years later in 2012, making London the first city to host the games thrice, and the only such city until Paris and Los Angeles host their third games in 2024 and 2028, respectively. The 1948 Olympic Games were also the first of two summer Games held under the IOC presidency of Sigfrid Edström.

The Summer Olympic Games, also known as the Games of the Olympiad, and often referred to as the Summer Olympics, is a major international multi-sport event normally held once every four years on leap years. The inaugural Games took place in 1896 in Athens, Greece, and the most recent Games were held in 2021 in Tokyo, Japan. The International Olympic Committee (IOC) is responsible for organising the Games and for overseeing the host city's preparations. The tradition of awarding medals began in 1904; in each Olympic event, gold medals are awarded for first place, silver medals for second place, and bronze medals for third place.The Winter Olympic Games were created out of the success of the Summer Olympic Games, which are regarded as the largest and most prestigious multi-sport international event in the world.