Who led the first successful expedition to reach the South Pole?

Roald Amundsen led the first successful expedition to reach the South Pole.

Amundsen and four companions reached the pole on 14 December 1911, nearly five weeks before Robert Falcon Scott's British expedition. The Norwegian team travelled with dogs and used skis, methods that were well suited to Antarctic conditions and helped them conserve supplies.

Amundsen had originally planned an Arctic expedition, but he changed his goal after learning that Robert Peary claimed to have reached the North Pole in 1909. He kept his Antarctic destination secret from much of the public until his ship was already under way. His expedition established a depot system and carefully planned its route across the ice.

Scott's party reached the South Pole on 17 January 1912 and died during the return journey. The achievement is sometimes confused with the first expedition to cross Antarctica, which was Ernest Shackleton's Imperial Trans-Antarctic Expedition of 1914–1917, completed by its support parties rather than by reaching the pole first.