Thor and Margrét moved to
Akranes where Thor started a shop. Business went well at first, but around 1900 Thor was bankrupted when a ship carrying his goods was lost. Thor moved with his family to
Hafnarfjörður where they lived until Thor got back on his feet and established a new shop in
Reykjavík. Fishing at this time in Iceland was in transition from being 'a secondary occupation for farmers' to being 'an industry in its own right'. Thor was known for his energy and 'two of the most powerful fishing businessmen in
Seltjarnarnes, Guðmundur Einarsson í Nesi and Þórður Jónasson í Ráðagerði, said that they would buy fishing equipment from him if he offered it at a competitive price'. Guðmundur gave Thor the use of his premises on the corner of
Austurstræti and Veltusund in Reykjavík, and both he and Þórður invested 500
krónur to start the company. Thor called the company Godthaab-verzlunin after the street
Godthaabsvej in
Frederiksberg in Copenhagen. The company did well and Thor was soon the richest person in Iceland. In 1908 he built himself a splendid house at Fríkirkjuvegur 11, by
Tjörnin, now in the Hallargarður sculpture park. With
Pétur J. Thorsteinsson, Thor was a founder member of the fishing and fish-processing company PJ Thorsteinsson & Co, otherwise known as the
Milljónarfélagið, in 1907. The company's name came about because it aimed to achieve a share capital of ISK1m, which would have equalled Iceland's state budget---though that goal was never quite achieved. Through it, Thor took a role in the design of the Jóni forseti, Iceland's first trawler; established a harbour at
Viðey; and built
Iceland's only railway line. Pétur and Thor got on badly; Pétur left, and four years later, the company was bankrupt; both partners lost money, but Pétur the more. 'At the time, there was an investigation into the affair, where Jensen famously couldn't remember a thing about the whole debacle.' Later, in his autobiography, Jensen argued, implausibly, that the bankruptcy was in no way his fault. He was also a founder member of
Eimskip but was not elected to the board on account of his origins, and took no further role in the company. In later years Thor focused on making Korpúlfsstaður the largest dairy in Iceland. He put considerable resources behind this and achieved his goal. Thor died one night after a
stroke. Out of respect, his numerous businesses closed the day of his funeral, which took place on 18 September 1947. ==Land purchases==