In August 1931, the Nazi
Party decided to have its own intelligence and security body. Heinrich
Himmler therefore created the SD (Sicherheitsdienst). Reinhard
Heydrich was appointed head of the organization and it was kept
distinct from the uniformed SS (Schutzstaffel).
When Adolf Hitler became
chancellor in 1933, the SD was given extra power to deal with all opposition
to the Nazi government. On June 29-30, 1934, the SD played an important
role in the Night of the Long
Knives.
In 1936, Reinhard Heydrich became head of the SD and the Gestapo.
On the outbreak of the Second World War, both of these organizations
became part of the Reich Security Administration (RSHA). After Heydrich
was assassinated in 1942, Heinrich
Himmler became the leader of the SD. The following year he was replaced
by Ernst Kaltenbrunner.
There was great competition between the SD and the German military
intelligence organization, Abwehr.
In June 1944, Himmler took over Abwehr and, after
the July Plot the organization
was absorbed into the SD.
At the Nuremberg War Crime
Trials, the SD (Sicherheitsdienst) was declared a criminal organization
and membership of it made its men liable to prosecution.