On 18 June 1940, German Wehrmacht soldiers captured Jean-René Vidal in Laval, in the north-west of France. From there, in mid-November, he was sent by train via Châlons, Metz and Leipzig to a prisoner of war camp at Fürstenberg (Oder). On 26 November 1940, he arrived at camp 301 of Stalag IIID in Berlin. He was forced to work first for the Berlin water utilities company, then for three years at Berliner brickworks, including as a carpenter. In five years, he was in thirteen different camps all over Berlin.

Jean-René Vidal was one of 20,000 French prisoners of war held in Berlin. They were protected by the Geneva Conventions, with the International Red Cross monitoring their living and working conditions. This protection ended in the autumn of 1943 when the Wehrmacht stripped them of the status of prisoners of war, including Jean-René Vidal, and changed it to that of civilian forced labourers. His working hours were extended and he had to travel to work by public transport. The journey could take up to two hours in each direction because of the heavy bomb damage.

Jean-René Vidal wrote down everything he experienced in notebooks. Almost every day he recorded his 10 to 12 hours of work, six days a week. He described where he had to work, how the labour detachments were transported to work, his accommodation, his contacts with fellow prisoners, his food, his illnesses, his free time, when parcels or letters arrived, how long they took to arrive, what they contained or what he might have wished for. The longer the war went on, the more night air raids he mentioned. In May 1941, he sketched the stations on the city train line he used to travel from his accommodation camp in Grünau to his workplace in Lichtenrade, where his unit was working in a market garden.