The main purpose of the many purges and public trials that took place in the Soviet Union in the 1930s was to eliminate opposition to Joseph Stalin and his government.
Joseph Stalin created his dictatorship in Russia by ruling with ideologies of Marxism-Leninism. He removed all the opposition to communism by sending the leaders to exile.
Therefore, the trials and purges were held to demonstrate the brutality of Stalin to build terror in opposition leaders.
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