Final answer:
The event described in the question is the October Revolution in Russia. It was a turning point in Russian history, resulting in the establishment of a communist regime.
Step-by-step explanation:
The event described in the question is the October Revolution in Russia. This revolution was a key turning point in Russian history, during which the Bolshevik Party, led by Vladimir Lenin, overthrew the provisional government and established a communist regime. The revolution involved the assassination of the leader of the provisional government and a takeover of the Duma. It led to significant changes in Russian society and politics, including the emergence of a new economic and social system based on communism.