Some reasons that caused Russia to become communist

In Russia, efforts to build communism began after Tsar Nicholas II lost his power during the February Revolution, which started in 1917, and ended with the dissolution of the USSR in 1991.

Explanation:

Communism (from Latin communis, 'common, universal')[1][2] is a philosophical, social, political, and economic ideology and movement whose ultimate goal is the establishment of a communist society, namely a socioeconomic order structured upon the ideas of common ownership of the means of production and the absence of social classes, money,[3][4] and the state.[5][6] As such, communism is a specific form of socialism.

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the right answer is the end of world war ii

after the end of a global wwii all the nations involved, in an attempt to create an organization to maintain world peace. this agreement would work settling international disputes via negotiation and arbitration instead of leading the issues escalate to another war.