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The United States of America (USA), represented by the United States Olympic Committee (USOC), competed at the 2008 Summer Olympics in Beijing, China. U.S. athletes have competed in every Summer Olympic Games in the modern era, except the 1980 Summer Olympics in Moscow, which was boycotted by the American team and 65 other countries in protest of the Soviet invasion of Afghanistan. The USOC sent a total of 588 athletes to Beijing (310 men and 286 women), and competed in all Olympic sports except handball.
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China was the host nation of the 2008 Summer Olympics. China was represented by the Chinese Olympic Committee (COC), and the team of selected athletes were officially known as Team China.
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The Kazakhstan men's national water polo team is the representative for Kazakhstan in international men's water polo.
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Australia competed at the 2012 Summer Olympics in London, from 27 July to 12 August 2012. Australian athletes have competed in every Summer Olympic Games of the modern era. The Australian Olympic Committee sent a total of 410 athletes to the Games to compete in 23 sports.
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Spain competed at the 2012 Summer Olympics in London, from 27 July to 12 August 2012. This nation has competed in all but two Summer Olympic Games since its official debut in 1920. Spain boycotted two editions, the 1936 Summer Olympics in Nazi Germany and the 1956 Summer Olympics in Melbourne, as a protest against the Soviet invasion of Hungary. In 2012, the Spanish Olympic Committee sent the nation's smallest delegation to the Games since 1988. A total of 278 athletes, 166 men and 112 women, competed in 23 sports.
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Hungary competed at the 2012 Summer Olympics in London, from 27 July to 12 August 2012. Hungarian athletes have competed at every Summer Olympic Games in the modern era, except the 1920 Summer Olympics in Antwerp, and the 1984 Summer Olympics in Los Angeles because of the Soviet boycott. The Hungarian Olympic Committee sent the nation's smallest delegation to the Games since 1956. A total of 159 athletes, 97 men and 62 women, competed in 18 sports.
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The Russian Federation competed at the 2012 Summer Olympics in London, United Kingdom, from 27 July to 12 August 2012. This was the nation's fifth consecutive appearance at the Summer Olympics as an independent nation. The Russian Olympic Committee sent a total of 436 athletes to the Games, 208 men and 228 women, to compete in 24 sports. For the first time in its Olympic history, Russia was represented by more female than male athletes.
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Iceland competed at the 2012 Summer Olympics in London, from 27 July to 12 August 2012. The nation celebrated its centennial anniversary in the Olympics, having participated at every games since 1912, except for four occasions.
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Japan was the host nation of the 2020 Summer Olympics in Tokyo, originally scheduled to take place from 24 July to 9 August 2020 but postponed to 23 July to 8 August 2021 because of the COVID-19 pandemic. Since the nation's official debut in 1912, Japanese athletes have appeared at every Summer Olympic Games in the modern era, except for the 1948 Summer Olympics in London, to which they were not invited due to the nation's role in World War II, and the 1980 Summer Olympics in Moscow, as part of the United States-led boycott. The opening ceremony flag-bearers for Japan are basketball player Rui Hachimura and wrestler Yui Susaki. Karateka Ryo Kiyuna is the flag-bearer for the closing ceremony.
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Slovenia competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. This was the nation's eighth consecutive appearance at the Summer Olympics as an independent nation. Slovenian athletes won five medals, including three gold, won by canoeist Benjamin Savšek, road racing cyclist Primož Roglič, and sport climber Janja Garnbret. Three gold medals is an all-time record for Slovenia at the Summer Olympics, having previously won two gold in 2000. The Olympics saw the debut of the men's basketball team who finished fourth in the tournament.
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South Korea competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic.
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The People's Republic of China competed at the 2020 Summer Olympics in Tokyo, Japan. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021 because of the COVID-19 pandemic. It was the nation's eleventh appearance at the Summer Olympics since its debut in 1952. The opening ceremony flag-bearers for China are volleyball player Zhu Ting and taekwondoin Zhao Shuai. Sprinter Su Bingtian, who broke the Asian record of 100m during the Games, is the flag-bearer for the closing ceremony. The delegation competed in all sports except baseball (softball), handball, and surfing.
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Australia competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. Australia is one of only five countries to have sent athletes to every Summer Olympics of the modern era, alongside Great Britain, France, Greece, and Switzerland.
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Italy competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. Italian athletes have appeared in every Summer Olympics edition of the modern era, with the disputed exception of the 1904 Summer Olympics in St. Louis where one Italian may have participated.
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France competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. French athletes have appeared in every Summer Olympic Games of the modern era, alongside Australia, Great Britain, Greece, and Switzerland. As Paris will host the 2024 Summer Olympics, France was the penultimate nation to enter the stadium, alongside the United States which will host the 2028 Summer Olympics in Los Angeles, before the host country Japan during the parade of nations at the opening ceremony. Additionally, a French segment was performed in Paris and some pre-recorded events at the closing ceremony as performers did not travel to Tokyo due to the travel restrictions related to the pandemic. However, Paris mayor Anne Hidalgo was the only delegation present at the ceremony.
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Germany competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. It was the nation's eighth consecutive appearance at the Summer Olympic Games after its reunification in 1990.
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The United States of America (USA), represented by the United States Olympic & Paralympic Committee (USOPC), competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place in the summer of 2020, the Games were postponed to July 23 to August 8, 2021, due to the COVID-19 pandemic. U.S. athletes have appeared in every Summer Olympic Games of the modern era, with the exception of the 1980 Summer Olympics in Moscow, which the U.S. boycotted in protest of the Soviet invasion of Afghanistan. The opening ceremony flag-bearers for the United States were baseball player Eddy Alvarez and basketball player Sue Bird. Javelin thrower Kara Winger was the flag-bearer for the closing ceremony. For the third consecutive time in the Summer Olympics, the United States was represented by more female than male athletes (285 men and 330 women).
Prior to the 2019 decision by the World Anti-Doping Agency (WADA), the Russian Federation was expected to compete at the 2020 Summer Olympics in Tokyo, which took place from 23 July to 8 August 2021 because of the COVID-19 pandemic. It would have been the country's seventh consecutive appearance at the Summer Olympics as an independent nation; however, their athletes were entered by and represented the "Russian Olympic Committee", using the acronym "ROC", due to the consequences of the doping scandal in the country.
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Russian athletes competed at the 2022 Winter Olympics in Beijing, China, from 4 to 20 February 2022, under the "Russian Olympic Committee" designation due to the consequences of the doping scandal in the country.
This article shows the rosters of all participating teams at the men's basketball tournament at the 2020 Summer Olympics in Tokyo.