Joachim Rønneberg
Saboteur who led the daring 1943 raid on the Nazis’ heavy water plant in the Telemark mountains
JOACHIM RØNNEBERG, who has died aged 99, was only 23 when he was chosen to lead a raid intended to stop Nazi Germany’s attempt to create a nuclear bomb. On the night of February 16 1943, Rønneberg led a six-man team of Norwegian commandos who parachuted from 1,000ft on to the Telemark plateau in southern Norway, to join a four-man reconnaissance team and attack a Nazi-controlled hydroelectric plant producing deuterium oxide or “heavy water”. This, the Allies feared, could be used in the German production of nuclear weapons.
The enemy had been alerted by an earlier, failed raid by British commandos and the plant had been reinforced by extra guards, lights, barbed wire, guns and mines. Despite having been dropped in the wrong place, and fierce snowstorms which kept the team weather-bound for several days, one hour before midnight on February 27 Rønneberg and his saboteurs climbed down a gorge, crossed an ice-choked river, scrambled up the rock face on the other side, and entered the plant along a railway track, cutting through a gate and a fence.
He and Fredrik Kayser climbed a stairway to a cable duct in the wall, and followed the cable tunnel into the electrolysis facility. There they surprised a guard and locked him up. Joined by two other Norwegians, who had broken in by another route, “two of us set the explosive charges. The fuses were about two minutes long. I cut them down to 30 seconds and lit them”, recalled Rønneberg. They then escaped, locking the door behind them.
The sound of the charges blowing was heard as a thud over the deep hum of the generating machinery, but the German guards seem to have believed that the weight of snow had set off one of their own landmines. Rønneberg watched as one guard sauntered out of a hut, tried the door to the electrolysis facility, found it locked, shone a torch along the ground, gave up and went back into the guardhouse without realising that half a dozen Tommy guns were pointed at him.
Once the Germans realised what had happened, thousands of soldiers were brought in, but an extensive organised search failed to find the saboteurs, who under the cover of darkness and deep snow, were already far away. Rønneberg and the explosives team, fully armed and in uniform, skied over the high plateau and across the valleys of eastern Norway to Sweden, 250 miles away: the operation was completed without firing a shot.
By March 29 Rønneberg and his team were back in London.
The raid on the heavy water plant at Vemork was one of the most important sabotage actions of the Second World War, and such a stunning success that it is still in the curriculum for today’s Special Forces. Though Rønneberg was regarded as one of the great heroes of the war, he said: “We just did a job. We got lucky. Certainly luck, but also very good intelligence about the target. Maybe the pulse was a bit higher than normal, but it was just a question of setting the charges and getting away as quickly as possible”.
There were many rewards for the team, Rønneberg receiving the DSO from the British and Norway’s highest decoration for military gallantry, the War Cross with sword.
One of three brothers, Joachim Holmboe Rønneberg was born on August 30 1919 into a prominent merchant family in the city of Ålesund, where his great-great-grandfather had established a business in 1812. Young Joachim had completed his schooling and taken the exams for entry to Oslo university, but he was not studious and preferred mountain climbing to reading. He was working in a fishing company and waiting for the summer conscription to join the navy, when the Germans invaded in April 1940.
In March 1941, telling no one and leaving a farewell letter to his parents, Rønneberg took the “Shetland Bus” on a 24-hour crossing in a 45-foot fishing boat to Shetland. A few days later in London he met the Norwegian actor Martin Linge, who was also leader of No 1 Norwegian Independent Company, also known as Lingekompaniet, sponsored by the Special Operations Executive. In the next few months Rønneberg rose from student to instructor in explosive demolitions and displayed natural leadership, until in December 1942, just as he was beginning to become impatient, he was given command of Operation Gunnerside, as the Telemark raid was officially known, (named after the village where the head of SOE, Sir Charles Hambro, used to shoot grouse).
After the raid, the Prime Minister Winston Churchill asked: “What rewards are to be given to these heroic men?” But Rønneberg was a modest man and all he wanted to do was return to his beloved Norway. Less than a year later he and two others were dropped into Romsdal to continue their campaign of sabotage against the Germans.
For nearly a year they lived in a makeshift hut under a cliff. Their survival was threatened by a shortage of supplies, but in January 1945 they blew up a bridge, which stopped German railway traffic through the Romsdal for three weeks. Only a stomach illness obliged Rønneberg to be evacuated to England before the war ended.
Postwar, he returned to his hometown of Ålesund where he became a radio journalist, and eventually editorial director at a local radio and television station, before retiring in 1987.
Rønneberg was reticent when asked about his wartime experiences, and it was not until his 70s that he began to share his stories, especially on visits to schools, his message being that people needed to know their history so that they could make the right choices in the future. “Those growing up today”, he said, “have to understand that we must always be willing to fight for peace and freedom.” He was critical of Norway’s and the West’s presentday defensive preparations. Asked to comment in 2010 on the film The Heroes of Telemark (1965), he dismissed it as “hopeless”.
On his 95th birthday a statue of Rønneberg was unveiled in his hometown, where until recently he could be found every Saturday morning sitting by the window of his favourite café.
In 1949 he married Liv Foldal, who died in 2015. Their three children survive him.
Joachim Rønneberg, born August 30 1919, died October 21 2018