Background
Siem was born in Trondheim to Martin Olsen Siem and Gjertrud Christlock.
Businessman naval officer officer Knight
Siem was born in Trondheim to Martin Olsen Siem and Gjertrud Christlock.
Siem took actively part in local politics, and was elected to the municipal council in Horten (1925–1928), Tromsø (1931–1934) and Hadsel (1937–1940). He was director of Troms Fylkes Dampskibsselskap from 1929 to 1934, and of Vesteraalens Dampskibsselskab from 1936 to 1950. During the Battles of Narvik in 1940 he served with the 6th Division, as head of the sea transport.
During the German occupation of Norway he was among the resistance pioneers in Northern Norway.
He was incarcerated at Åneby/Grini from April to July 1941, as a "Svolvær hostage". He was later arrested by the Gestapo in December 1942, but was transferred to the Wehrmacht as prisoner-of-war in 1943 when about 1,100 Norwegian military officers were sent to prisoner-of-war camps in Poland and Germany for the rest of the war.