Nam Sung-yong (November 23, 1912 – February 20, 2001) was a Korean Olympian who won a bronze medal in the marathon at the 1936 Summer Olympics, completing the run in 2 hours, 31 minutes, and 42 seconds.
He was born in Junten (Suncheon), Korea, Empire of Japan and received higher education in Japan. Like the gold medalist Sohn Kee-chung, Nam Sung-yong used the Japanese pronunciation of his name, Nan Shōryū as Korea was then a part of the Japanese Empire.
The Republic of Korea (commonly known as South Korea) first participated at the Olympic Games in 1948, and has sent athletes to compete in every Summer Olympic Games since then, except for 1980 which they boycotted. South Korea has also participated in every Winter Olympic Games since 1948, except for the 1952 games.
The first ethnic Korean athletes to win medals did so at the 1936 Summer Olympics in Berlin, when Sohn Kee-chung and Nam Sung-yong won gold and bronze respectively in the men's marathon as members of the Japanese team. As Korea was under Japanese rule at that time, making them both Japanese subjects, the IOC credits both medals to Japan.
View the full Wikipedia page for South Korea at the Olympics