[1][6] His family subsequently relocated to nearby Sandefjord, the home of the Norwegian whaling industry, where at the young age of 9 he went to sea in a small barque with his father chasing seals and trading across the North Atlantic with Britain, returning to go to school during the fall and winter.

He continued this for a number of years, until his curiosity for the sea was so strong he enrolled himself in navigation school where he passed the exam for foreign-going mate at the age of 18.

Larsen was eager to get work as an officer on a ship, but due to economic difficulties in Norway at the time, he could not achieve that.

The Jason was a ship Larsen was familiar with as he had been aboard it during the voyage that carried Fridtjof Nansen to Greenland during his east–west crossing in 1888.

His expedition also discovered fossilised plant remains on Seymour Island,[11] and was the first to return fossils from the region;[10] the site has continued to yield significant paleontological results.

[12] The sea ice was heavier than in 1893, and – although the ship passed through the iceberg-infested Antarctic Sound now named after it – the expedition was unable to get further south than Snow Hill Island.

[10] Larsen spent the southern winter exploring South Georgia, where he found a sheltered harbour, a supply of fresh water, and an abundance of whales.

[10] Returning south in December 1902 to collect Nordenskjöld’s party, Larsen found Antarctic Sound choked with ice.

Before attempting the more treacherous route around Joinville Island, Larsen therefore left three men (Duse, Andersson and Grunden)[11] at Hope Bay with instructions to sledge south, contact Nordenskjöld’s team, and bring them back to Snow Hill Island in case the Antarctic was unable to reach them.

[11] The pack ice was thick in the Weddell Sea and Larsen, trapped several times, was eventually unable to free his ship.

With summer, in late 1903, the three men at Hope Bay decided to make another attempt to reach Nordenskjöld; his location was known to potential rescuers, while theirs was not.

Larsen was also instrumental, with his brother, in introducing Reindeer to South Georgia in 1911, as a resource for recreational hunting for the people involved in the whaling industry.

Larsen, like other managers and senior officers of the South Georgia whaling stations, lived in Grytviken together with his family including his wife, three daughters and two sons.