General Secretary of the Communist Party of the Soviet Union more than determine party membership composition. Stalin, its first incumbent, used the principles of democratic centralism to transform his office into that of party leader, and later leader of the Soviet Union. In 1934, the 17th Party Congress refrained from formally re-electing Stalin as General Secretary. However, Stalin was re-elected into all other positions and remained leader of the party without diminishment. In the 1950s, Stalin increasingly withdrew from Secretariat business, leaving the supervision of the body to Georgy Malenkov, possibly to test him as a potential successor. In October 1952, at the 19th Party Congress, Stalin restructured the party's
Joseph Stalin May, Stalin replaced Molotov as Premier of the Soviet Union. In June 1941, Germany invaded the Soviet Union, initiating the war on the Eastern Front. Although intelligence agencies had repeatedly warned him of Germany's intentions, Stalin was taken by surprise. He formed a State Committee of Defence, which he headed as Supreme Commander, as well as a military Supreme Command (Stavka), with Georgy Zhukov as its Chief of Staff. The German tactic of "blitzkrieg" was initially highly effective; the Soviet air force in the western borderlands was destroyed within two days. The German Wehrmacht pushed deep into Soviet territory; soon,