Vladimir Ilyich Ulyanov, better known by the name Lenin (April 22, 1870 – January 24, 1924), was a Marxist leader who served as the key architect of the October Revolution, and the first leader of the Soviet Russia.

Lenin’s original conversion to Marxism stemmed from a profound sense of disappointment and disdain for Tsarist rule. What was meant to evolve into a society free from class distinction became a society that was dominated by the political apparatus created by a revolutionary vanguard that clung to its power with more violence than the previous political elite had.

A Marxist theoretician, he believed that Communism's expansion into the rest of the world would be achieved through struggles of national liberation beginning not with the working class of the elite nations of Europe but through a reformed view of the oppressed class that could include intellectuals, workers and peasants. 

Joseph Stalin was the dictator of the Union of Soviet Socialist Republics (USSR) from 1929 to 1953. 

Under Stalin, the Soviet Union was transformed from a peasant society into an industrial and military superpower. However, he ruled by terror, and millions of his own citizens died during his brutal reign. 

Joseph Stalin was born Josef Vissarionovich Djugashvili in December 1878. When he was in his 30s, he took the name Stalin, which means “man of steel” in Russian. 

Stalin grew up poor and an only child. His father was a shoemaker and an alcoholic who beat his son, and his mother was a laundress. Stalin earned a scholarship to attend a seminary in the nearby city of Tblisi and study for the priesthood in the Georgian Orthodox Church. Stalin was interested in the revolutionary movement against the Russian monarchy. In 1899, Stalin was expelled from the seminary for missing exams, although he claimed it was for Marxist propaganda.

After leaving school, Stalin became an underground political agitator, taking part in labor demonstrations and strikes. He joined the more militant wing of the Marxist Social Democratic movement, the Bolsheviks, led by Vladimir Lenin. Stalin also became involved in various criminal activities, including bank heists, the proceeds from which were used to help fund the Bolshevik Party. He was arrested multiple times between 1902 and 1913, and subjected to imprisonment and exile in Siberia.