The "History of Soviet Russia and the Soviet Union" reflects a period of change for both Russia and the world. Though the terms "Soviet Russia" and "Soviet Union" are synonymous in everyday vocabulary, when we talk about the foundations of the Soviet Union, "Soviet Russia" refers to the few years after the abdication of the crown of the Russian Empire by Tsar Nicholas II (in 1917), but before the creation of the Soviet Union in 1922. Early in its conception, the Soviet Union strived to achieve harmony among all peoples of all countries. The original ideology of the state was primarily based on the works of Karl Marx and Friedrich Engels. In its essence, Marx's theory stated that economic and political systems went through an inevitable evolution in form, by which the current capitalist system would be replaced by a socialist state before achieving international cooperation and peace in a "Workers' Paradise," creating a system directed by what Marx called "Pure Communism."