At first, after Stalin died Georgi Malenkov became Prime Minister of the USSR and Nikita Khrushchev became General Secretary of the Communist Party. In the USSR, the real power was in the Communist Party, so Khrushchev was able to force Malenkov out, take over both positions and become the sole leader.
Prince Georgy Lvov took over immediately after Nicholas II abdicated. He was head of Russia's Provisional Government for three months then resigned and Alexander Kerensky took over. He led the country until Vladimir Lenin overthrew it and took over in the October Revolution.
Vladimir I. Lenin became leader of Russia after the Bolshevik Revolution.
Vladimir Putin was the leader of Russia after Boris Yeltsin.
Stalin died in 1953 and his place was taken by Nikita Khrushchev. He was the leader of Soviet Union till 1964.
Leonid Brezhnev
It was Nikita Kruschev.
Joseph Stalin (Iosef Vissarionovich Dzhugashvili) was Premier from 1922 until his death in 1953.
lenons death.
Stalin was Premier from 1924 to his death in 1953.
Joseph Stalin was the "totalitarian" leader of the Soviet Union after Lenin, however he did not have dictatorial powers immediately after Lenin's death in 1924. It took Stalin until the mid 1930's before he had eliminated almost all of his equals in the Communist Party and installed people loyal to him personally in positions of power. Once he had done that he became the totalitarian leader that history remembers him as.
improved for a while, but then became more strained
The more direct answer is that Joseph Stalin was the de facto dictator of the USSR in 1936 and even several years before that. Yes he held various titles, but that was for "show". Stalin had eliminated all left wing opposition by the late 1930's and ruled as a dictator.
Vladimir Lenin served as leader of soviet Russia from 1917 till his death in 1924. From 1922 he also served as Premier of the Soviet Union and was later succeeded by the famous communist leader Stalin.
Nikita Khrushchev Immediately after Stalin's death, Georgy Malenkov became the Premier of the Soviet Union while Nikita Khrushchev became First Secretary of the Communist Party. Both were in a position to wield authority, so the two ruled together in an uneasy alliance. About 2 years later, Malenkov was forced to resign and Khrushchev was able to oust all other rivals for power and take it for himself until he was deposed.
Stalin wan't a president, he was the 'General Secretary of the Soviet Union'. But he was the de facto leader from 1924 after Lenin's death, until his own death in 1953. By the way; its the Soviet Union, not 'reunion'.
After the death of Lenin
Joseph Stalin led the Soviet Union. Stalin took over after Lenin died. Stalin was not Lenin's choice as a successor but Stalin schemed and came into power, basically he stole the title. He was in power before and after WW11. He died in 1953. In WW2 he had signed a non-agression pact with Hitler, but ultimately became allied with France, Great Britain, the United States and the other Allied countries.
Stalin held several official titles:Chairman of the Council of MinistersGeneral Secratary of the Soviet Union Communist PartyPeople's Commissar for the Defense of the Soviet Union