Mauritania competed at the 2004 Summer Olympics in Athens, Greece, from 13 to 29 August 2004. The country's participation at Athens marked its sixth appearance in the Summer Olympics since its debut in the 1984 Summer Olympics. The delegation included two track and field athletes, Youba Hmeida and Aminata Kamissoko, who were both selected by wildcards after both failed to meet either the "A" or "B" qualifying standards. Hmeida was selected as the flag bearer for the opening ceremony. Neither of the Mauritanians progressed beyond the heats.
During the Parade of Nations portion of the 2004 Summer Olympics opening ceremony, athletes from each country participating in the Olympics paraded in the arena, preceded by their flag. The flag was borne by a sportsperson from that country chosen either by the National Olympic Committee or by the athletes themselves to represent their country.
2014 Winter Olympics Parade of Nations was part of the opening ceremony at the 2014 Winter Olympics. The national team from each nation participating in the Olympic Games was preceded by their national flag flag bearer into Fisht Olympic Stadium in the host city of Sochi, Russia. The flag bearer was an athlete of each national delegation chosen, to represent the athletes, either by the National Olympic Committee or by the national team.
During the Parade of Nations within the Rio de Janeiro 2016 Summer Olympics opening ceremony, athletes and officials from each participating team marched in the Maracanã Stadium preceded by their flag and placard bearer. Each flag bearer had been chosen either by the team's National Olympic Committee or by the athletes themselves.
During the closing ceremony of the 2020 Summer Olympics in Tokyo, the flag bearers for the 205 National Olympic Committee's (NOCs) and the IOC Refugee Olympic Team entered the Olympic Stadium. The flags of each country were not necessarily carried by the same flag bearer as in the opening ceremony. Due to COVID-19 related protocols, athletes had to leave Japan within 48 hours from completion of their final event, leaving some countries without representation during the closing ceremony. Flags of the countries without athletes present were instead carried by volunteers.
Russian Empire (1900–1912)
Soviet Union (1952–1988)
Unified Team (1992)
ROC (2020–2022)
Individual Neutral Athletes (2024)
