Kazakhstan competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's third appearance at the Summer Olympics in the post-Soviet era.
Russia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's third consecutive appearance at the Summer Olympics as an independent nation. The Russian Olympic Committee sent a total of 446 athletes to the Games, 244 men and 202 women, to compete in all sports, except baseball, field hockey, football, and softball.
Poland competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's eighteenth appearance at the Summer Olympics, except the 1984 Summer Olympics in Los Angeles, because of the Soviet boycott. The Polish Olympic Committee sent a total of 194 athletes to the Games, 132 men and 62 women, to compete in 21 sports. Men's volleyball was the only team-based sport in which Poland had its representation in these Olympic Games. There was only a single competitor in women's taekwondo.
Spain competed at the 2004 Summer Olympics in Athens, Greece, from August 13 to 29, 2004. This nation has competed in every Summer Olympic games since its official debut in 1920. Spain, however, boycotted two editions, the 1936 Summer Olympics in Nazi Germany, and the 1956 Summer Olympics in Melbourne, as a protest to the Soviet invasion of Hungary. The Spanish Olympic Committee sent the nation's third largest delegation in history to the Games. A total of 317 athletes, 177 men and 140 women, competed in 26 sports.
Hong Kong competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. It was the territory's thirteenth appearance at the Olympics and, at the opening ceremony, its team was the last to enter the stadium before the host nation because of the use of the Greek alphabet.
Czech Republic competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's third appearance at the Summer Olympics after gaining its independence from the former Czechoslovakia. The Czech Olympic Committee sent the nation's largest team to the Games since the post-Czechoslovak era. A total of 142 athletes, 80 men and 62 women, competed in 19 sports; the nation's team size was roughly denser from Sydney by one sixth of the athletes. Women's basketball was the only team-based sport in which the Czech Republic had its representation at these Olympic Games. There was only a single competitor in equestrian, artistic and trampoline gymnastics, judo, and weightlifting.
Slovenia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's fourth consecutive appearance at the Summer Olympics since the post-Yugoslav era. The Slovenian Olympic Committee sent the nation's largest ever delegation to the Games in Olympic history. A total of 79 athletes, 56 men and 23 women, competed in 10 sports. For the second consecutive time, men's handball was the only team-based sport in which Slovenia had its representation at these Games.
Norway competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's twenty-fourth appearance at the Summer Olympics, except for the 1904 Summer Olympics in St. Louis, and the 1980 Summer Olympics in Moscow, due to the country's support of the United States boycott. With the absence of women's football and handball teams, Norwegian Olympic and Paralympic Committee and Confederation of Sports sent the nation's smallest delegation to the Games since the 1968 Summer Olympics in Mexico City. A total of 53 athletes, 36 men and 17 women, competed only in 12 different sports. There was only a single competitor in badminton, swimming, taekwondo, weightlifting, and wrestling.
Hungary competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. 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 a total of 209 athletes to the Games, 119 men and 90 women, to compete in 20 sports. Water polo and handball were the only team-based sports in which Hungary had its representation in these Olympic Games. There was only a single competitor in road cycling and mountain biking.
Thailand competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's thirteenth appearance at the Olympics, except the 1980 Summer Olympics in Moscow because of its partial support to the United States boycott.
Peru competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's fifteenth appearance at the Olympics, except the 1952 Summer Olympics in Helsinki.
Latvia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's eighth appearance at the Summer Olympics.
Austria competed at the 2004 Summer Olympics in Athens, Greece from 13 to 29 August 2004. 74 competitors, 54 men and 20 women, took part in 56 events in 18 sports.
Serbia and Montenegro competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. Previously known as the Federal Republic of Yugoslavia, this was the nation's third and last joint appearance at the Summer Olympics before Serbia and Montenegro became separated independent states in 2006. The Olympic Committee of Serbia and Montenegro sent a total of 87 athletes to the Games, 80 men and 7 women, to compete in 14 sports. Men's basketball, football, volleyball, and water polo were the only team-based sports in which Serbia and Montenegro had its representation at these Games. There was only a single competitor in road cycling, judo, tennis, and wrestling.
Croatia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's fourth consecutive appearance at the Summer Olympics since the post-Yugoslav era. The Croatian Olympic Committee sent the nation's smallest delegation to the Games since its debut in 1992. A total of 81 athletes, 66 men and 15 women, competed in 14 sports. Men's water polo, and men's handball were the only team-based sports in which Croatia had its representation in these Olympic Games.
Uruguay competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's eighteenth appearance at the Olympics, except the 1980 Summer Olympics in Moscow, because of its partial support to the United States boycott.
Switzerland competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. Swiss athletes competed at every Summer Olympic Games in the modern era, except when they boycotted the 1956 Summer Olympics in Melbourne as a protest to the Soviet invasion of Hungary. The Swiss Olympic Association sent a total of 98 athletes to the Games, 59 men and 39 women, to compete in 18 sports.
Uzbekistan competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's third consecutive appearance at the Olympics. The National Olympic Committee of the Republic of Uzbekistan sent a total of 70 athletes to the Games, 52 men and 18 women, to compete in 13 different sports, tying its delegation record with Sydney four years earlier. There was only a single competitor in road cycling, artistic and trampoline gymnastics, and table tennis.
Macedonia competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. This was the nation's third consecutive appearance at the Summer Olympics in the post-Yugoslav era.
Slovakia competed in the 2012 Summer Olympics in London, from 27 July to 12 August 2012. This was the nation's fifth consecutive appearance at the Summer Olympics. The Slovak Olympic Committee sent a total of 47 athletes to the Games, 26 men and 21 women, to compete in 11 sports. There was only a single competitor in badminton, judo, triathlon, and weightlifting.
Hungary (1896–1912)
Czechoslovakia (1920–1992)
