The Red Orchestra, as it was known in Germany, was the name given by the Abwehr Section III.F to anti-Nazi resistance workers in August 1941. It primarily referred to a loose network of resistance groups, connected through personal contacts, uniting hundreds of opponents of the Nazi regime. These included groups of friends who held discussions that were centred on Harro Schulze-Boysen, Adam Kuckhoff and Arvid Harnack in Berlin, alongside many others. They printed and distributed prohibited leaflets, posters, and stickers, hoping to incite civil disobedience. They aided Jews and resistance to escape the regime, documented the atrocities of the Nazis, and transmitted military intelligence to the Allies. Contrary to legend, the Red Orchestra was neither directed by Soviet communists nor under a single leadership. It was a network of groups and individuals, often operating independently. To date, about 400 members are known by name.

The Abwehr was the German military-intelligence service for the Reichswehr and the Wehrmacht from 1920 to 1945. Although the 1919 Treaty of Versailles prohibited the Weimar Republic from establishing an intelligence organization of their own, they formed an espionage group in 1920 within the Ministry of Defence, calling it the Abwehr. The initial purpose of the Abwehr was defense against foreign espionage: an organizational role that later evolved considerably. Under General Kurt von Schleicher the individual military services' intelligence units were combined and, in 1929, centralized under Schleicher's Ministeramt within the Ministry of Defence, forming the foundation for the more commonly understood manifestation of the Abwehr.