Helmer Julius Hanssen (1870-1956) was a Norwegian polar explorer, and one of the first five to reach the South Pole on the expedition of Roald Amundsen.
Hanssen was born in Risøyhavn, a small village in the northern part of Norway. He was an experienced ice pilot, a skill he had learned while hunting seals around Spitsbergen.
From 1903 to 1905 Helmer Hanssen participated in Roald Amundsen's successful search for the Northwest passage, as second mate on board the ship Gjøa. On the expedition he learned from the Inuits how to drive sled dogs. In 1910 he headed south with Amundsen to conquer the South Pole. This time as an expert dog driver. He was also in charge of navigation, carrying the master compass on his sledge.
He was one of the first five people to reach the South Pole on December 14, 1911, along with Roald Amundsen, Olav Bjaaland, Oscar Wisting, and Sverre Hassel.
In 1919 he once again went north this time as captain on Maud in Roald Amundsen's Northeast Passage expedition.
In 1936 Hanssen published his autobiography The Voyages of a Modern Viking, London: Rutledge, 1936.
Helmer Julius Hanssen was awarded the Knight Class 2 of St. Olav for exceptional seamanship on Roald Amundsen's expeditions in the northern and southern parts of the world.