Jan Dahm
Norwegian resistance member who headed SIS radio station Theta.
Jan Dahm (5 April 1921 – 16 February 2013) was a Norwegian who resisted the German occupation during World War II. He was part of the earliest group tried by a German military court in Norway, and later founded and led the Secret Intelligence Service radio group Theta, active in Bergen from December 1941 to June 1942.
When Germany invaded Norway in April 1940, Dahm was a 19-year-old engineering student at Bergens Tekniske Skole. A longtime radio enthusiast and member of Bergen Radio Relé Liga, he had a home workshop for building radios. On 25 June 1940, while sitting an exam, he was taken to the Gestapo office in Bergen and shown equipment seized from his home; he was charged with espionage. Three days later, he was transported by bus with ten others from Bergen to Møllergaten 19 in Oslo.
The court-martial began in Oslo on 22 August 1940, conducted by the 3rd Senate of the Reich Military Tribunal from Berlin. The prosecutor demanded the death penalty for six defendants under German laws on espionage and treason. On 28 August, three were sentenced to death: agent Konrad Rendedal, Colonel Gabriel Lund, and Doctor Odd Solem. Jan Dahm and another defendant were acquitted due to lack of evidence, while policeman Erling Staff received five years in prison. These were the first death sentences in Norway since 1876, later commuted to five years’ fortress detention. Dahm was released but required to report to the Gestapo every two weeks.
Dahm resumed his studies but remained under Gestapo surveillance. He learned to evade his watchers and made contact with resistance figures, including physicist and radio expert Helmer Dahl and Milorg district leader Mons Haukeland. With friends, he prepared a hidden room in a building at Bryggen for use as a workspace. Given their radio skills, the group sought to contact Allied forces. Member Bjarne Thorsen sailed to Lerwick and connected with the Secret Intelligence Service in London, returning with a radio transmitter, codes, and schedules.
The station, named Theta, began transmitting in December 1941. Among its key reports was one on the battleship *Tirpitz*. The group operated until June 1942, when member Kristian Ottosen was arrested. Dahm then fled to Sweden via Bodø, Fauske, and Junkerdalen with fellow member Wenche Stenersen.
Quick Facts
- Birth Date
- 1921-04-05
- Death Date
- 2013-02-16
- Occupation
- Resistance member and engineer
Facts from the source article.
Lore & Background
At the German attack on Norway in April 1940, Jan Dahm was a nineteen-year-old engineering student at Bergens Tekniske Skole and an eager radio amateur. On 25 June 1940, while taking an examination, he was taken to the Gestapo office in Bergen and charged with espionage. He was transported to Oslo and faced a German court-martial on 22 August 1940. The prosecutor sought the death sentence, but on 28 August Dahm was set free as the charges could not be proved. He returned home but had to report to the Gestapo every two weeks.
Dahm continued his studies while under Gestapo supervision. He made contacts with undercover resistance members and prepared a secret room at Bryggen. Group member Bjarne Thorsen traveled to Lerwick and established contact with the Secret Intelligence Service, returning with a radio transmitter, codes, and schedules. The station, called Theta, began operating in December 1941 and transmitted reports including one on the battleship Tirpitz. The group operated until June 1942, when member Kristian Ottosen was arrested. Dahm then fled to Sweden with Wenche Stenersen, was taken to Britain for briefing, trained as a radar officer, and served at the naval base in Shetland.
Reader's Guide
Jan Dahm's significance lies in his role as a key figure in early Norwegian resistance against German occupation. He was among the first to face a German court-martial in Norway, a trial that resulted in the first death sentences in Norway since 1876. His acquittal allowed him to continue resistance work. As head of the Secret Intelligence Service group Theta, he established a vital radio link between occupied Bergen and Allied forces. Theta's transmission of intelligence on the battleship Tirpitz was a notable contribution to Allied naval operations. The group's operation from December 1941 to June 1942 demonstrated the feasibility of clandestine radio communication under occupation. After fleeing to Sweden and later serving as a radar officer in Shetland, Dahm returned to civilian life, graduating from Bergens Technical School in 1947 and running an engineering company from 1950. His legacy is that of a technically skilled amateur radio operator who applied his expertise to wartime intelligence work.
Did You Know?
- Jan Dahm was among the first group of people to be subject to a court-martial during the German occupation of Norway.
- The Theta group transmitted a report on the battleship Tirpitz.
- Dahm was acquitted in the court-martial because the charges could not be proved.
- After the arrest of Kristian Ottosen, Dahm fled to Sweden with Wenche Stenersen.
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