Nansen was born in the country near Oslo. He studied medicine and in 1897 became professor at Oslo University, followed by membership in the Russian Academy of Sciences.

In 1887-1888 he made the first ski crossing through Greenland where he lived with the Eskimos, learned their customs and ways of survival in the harsh climate. In the years 1893–1896 he went on his second expedition to the Arctic areas of Russia and made a failed attempt at exploring the North Pole on skis and a dog-pulled sledge.

Later he began his career in diplomacy and in 1920 he took the position of the first High Commissioner of the League of Nations for Refugees. He assisted stateless political refugees who had no documents flee the Soviet Russia. These refugees received special identity documents, the Nansen Passports which replaced regular passports.