The son of a teacher, Helmut Knochen studied philosophy and journalism. When he earned a PhD in 1934, he had already been a member of the Nazi party for two years. His military career advanced at lightning speed: in 1936, he was PERMANENT at the SD central office, where he analyzed the newspapers of German émigrés in France, Belgium and the Netherlands; the next year, he was head of sub-section II-11 in charge of “Churches, Jews and Freemasons,” where Adolf Eichmann and Theodor Dannecker – the main protagonists of anti-Jewish action – were under his authority. In 1939, Knochen joined the SD-Ausland (the German civilian foreign intelligence service), where amongst other things, he directed a large infiltration operation of a British Intelligence Service network in Holland. He received the Iron Cross, First-Class (a German military decoration), and permission to go establish Nazi police services in occupied France, with a small unit of around twenty men. Knochen was particularly in charge of monitoring opponents of the regime, Jews, Communists and Freemasons. His relationship with the Military Command was regularly marred by power struggles and crises, including the affair of the explosion of the synagogues in October 1941. In that episode, the Sipo-SD had provided explosives to the French collaborationists in charge of the operation without warning the Military Command staff. Though Otto von Stülpnagel requested that Knochen be recalled to Berlin, only the latter’s superior officer was actually penalized for this affair, whereas Knochen, who was close to Heydrich (Himmler’s deputy, the second-in-command of the Nazi police and head of the RSHA) and a remarkable organizer of police forces, kept his job.
The nomination of Carl Oberg as supreme leader of the SS and German police in France (Befehlshber der Sipo und des SD, or BdS) in March 1942, while Knochen, an able politician, remained head of the Sipo-SD, gave him the opportunity to show the full range of his talent. A pragmatic man, he relied on collaboration with the Vichy government as long as it allowed him to compensate for the limited size of his staff while keeping up with the schedules of the Nazi programs, particularly that of the “Final Solution.” Thus, he was one of the main architects of the “Bousquet-Oberg” accords. Though Knochen’s talent as an organizer and a negotiator were behind the successful launch of the “Final Solution,” he perceived the situation in occupied France in essentially political terms and focused on law enforcement and keeping order. He was concerned with ensuring that the German administration ran smoothly, especially with regard to the economic exploitation of France. But Heydrich’s death lost Knochen a protector and supporter. He was not close to Himmler, nor to Ernst Kaltenbrunner, the new head of the Reichssicherheitshauptamt or RSHA (Headquarters of the Reich Security Services, the Nazi police service). From that point on, Knochen’s political and collaborationist line was no longer always supported and followed. Nonetheless, upon a request from Berlin, he carried out harsher directives when the Allied landing became imminent.
Knochen was recalled to Berlin on August 18, 1944 when the SS left , and the end of his career was less prestigious. He was turned over to the French authorities in 1946 and sentenced to death on October 9, 1954 along with Carl Oberg, his former superior. He was pardoned in December 1962 and returned to Germany.