Claude Jaeger was born on April 2, 1917, in Geneva, Switzerland. He undertook his studies in Paris and briefly worked at the Ministry of Finance, but was interrupted by World War II and he served in the French Army. After the 1940 armistice with Nazi Germany, he joined the Communist Party of Spain (PCE) at the suggestion of Manuel Azcárate, a Spanish communist in exile in France after the Republican defeat in the Spanish Civil War. After the collapse of the Nazi-Soviet alliance, Germans began rounding up the exiled Spaniards in France in 1941. Jaeger and other communists sought refuge in the "Zone libre" (free zone) in the southern section of Vichy France in 1942. He also began to discover his interest in the film industry and worked as an assistant director. In the "Zone Libre", Jaeger met Gillo Pontecorvo, an Italian filmmaker and fellow communist, and joined the Italian Communist Party (PCI). By 1943, Jaeger also worked with the information service of the Francs-Tireurs et Partisans (FTP), the communist arm of the French Resistance. His codename / psuedonym was "Michelin" and he was given a rank of colonel, and served in the FTP until the war's end. Jaeger briefly worked under General Jean de Lattre de Tassigny's forces in 1945 after the FTP was merged with the Free French army. Afterward he joined the (OPC), the French regulator of cinema, which soon shed its Vichy origin by changing into the modern "Centre national du cinéma et de l'image animée" (CPC) in 1946. He worked as a production manager there until 1950, when his political leanings saw him dismissed. The French Communist Party (PCF) put Jaeger in charge of Procinex, a corporation that would create short films for left-wing audiences and for the Soviet sphere of influence. As these films were commissioned by a political party, they tended to be intended more on the educational, inspirational, and/or propaganda style rather than as pure entertainment.