He was born in Holmestrand as a son of ship-owner Hans Ludvig Lorentzen (1839–1904) and Thala Margrethe Bredrup (1847–1941).

In 1923 they had 5 sons and one daughter: Hans Ludvig Ph.D.; Per Arne; Ingjerd Ragna; Oivind Harald; Erik Finn; and Erling Lorentzen, who went on to marry Princess Ragnhild of Norway,[1] and had the children Haakon, Ingeborg and Ragnhild Lorentzen.

Olsen & Co. already at the end of the year, but Lorentzen became manager for the ship's South America service, organized through Den Norske Syd-Amerika Linje.

In 1920 Lorentzen advanced to CEO of Den Norske Syd-Amerika Linje, a position he left in 1938 to further his own shipping business.

Partly, the conflict was grounded in Lorentzen's engagements outside of Den Norske Syd-Amerika Linje.

In 1940, Norway was entangled in World War II, and the state reorganized the country's shipping into Nortraship.

Sobral claimed that Moss Værft & Dokk neglected their contract agreement regarding the construction of two vessels during the war.