Otto Cordes was a member of the team that won the first gold medal by a German water polo team at the Amsterdam Olympics. He took silver and bronze at the European Championships in 1931 in Paris and 1926 in Budapest, respectively. Playing for Hellas SC Magdeburg, Cordes was German Champion in 1924-26, 1928-31 and 1933. He was also a fast elegant swimmer and was German University Champion in the 100 metres freestyle 1924-27. In 1939, he was posted by his company to Brazil and stayed there during the outbreak of World War II. He was the father of Burkhard Cordes, who competed in sailing for Brazil in 1968 and 1972.