linguistic:paraphrasing
SA and SS

The Sturmabteilung (SA; Storm Detachment), or Brownshirts, founded in 1921, was the first paramilitary wing of the Nazi Party; their initial assignment was to protect Nazi leaders at rallies and assemblies. They also took part in street battles against the forces of rival political parties and violent actions against Jews and others. Under Ernst Röhm 's leadership the SA grew by 1934 to over half a million members—4.5 million including reserves—at a time when the regular army was still limited to 100,000 men by the Versailles Treaty.

Röhm hoped to assume command of the army and absorb it into the ranks of the SA. Hindenburg and Defence Minister Werner von Blomberg threatened to impose martial law if the activities of the SA were not curtailed. Therefore, less than a year and a half after seizing power, Hitler ordered the deaths of the SA leadership, including Rohm. After the purge of 1934, the SA was no longer a major force.

Initially a small bodyguard unit under the auspices of the SA, the Schutzstaffel (SS; Protection Squadron) grew to become one of the largest and most powerful groups in Nazi Germany. Led by Reichsführer-SS Heinrich Himmler from 1929, the SS had over a quarter million members by 1938. Himmler initially envisioned the SS as being an elite group of guards, Hitler's last line of defence. The Waffen-SS, the military branch of the SS, evolved into a second army. It was dependent on the regular army for heavy weaponry and equipment, and most units were under tactical control of the High Command of the Armed Forces (OKW). By the end of 1942, the stringent selection and racial requirements that had initially been in place were no longer followed. With recruitment and conscription based only on expansion, by 1943 the Waffen-SS could not longer claim to be an elite fighting force.

SS formations committed many war crimes against civilians and allied servicemen. From 1935 onward, the SS spearheaded the persecution of Jews, who were rounded up into ghettos and concentration camps. With the outbreak of World War II, the SS Einsatzgruppen units followed the army into Poland and the Soviet Union, where from 1941 to 1945 they murdered more than two million people, including 1.3 million Jews. A third of the Einsatzgruppen members were recruited from Waffen-SS personnel. The SS-Totenkopfverbände (death's head units) ran the concentration camps and extermination camps, where millions more were murdered. Up to 60,000 Waffen-SS men served in the camps.

In 1931, Himmler organised an SS intelligence service which became known as the Sicherheitsdienst (SD; Security Service) under his deputy, Heydrich. This organisation was tasked with locating and arresting communists and other political opponents. Himmler established the beginnings of a parallel economy under the auspices of the SS Economy and Administration Head Office. This holding company owned housing corporations, factories, and publishing houses.