The main causes of the Russian Revolution include widespread discontent with the Tsarist regime, economic hardship, and social inequality. The hardships caused by World War I, including military defeats and food shortages, exacerbated public frustration. The influence of Marxist ideologies and the failure of the government to address reforms further fueled revolutionary sentiments. Additionally, the February Revolution of 1917, which led to Tsar Nicholas II's abdication, set the stage for the Bolshevik takeover in October 1917, resulting in the establishment of a communist government.