What was the name of the early Russian communists who played a key role in the October Revolution?

The early Russian communists who played a pivotal role in the October Revolution were called the Bolsheviks. This faction, led by figures such as Vladimir Lenin and Leon Trotsky, advocated for a radical approach to revolution, emphasizing the need for a vanguard party to lead the proletariat (working class) in overthrowing the existing government. Their successful seizure of power in October 1917 fundamentally transformed Russia, leading to the establishment of a communist state.

In contrast, the Mensheviks were more moderate and believed in a more gradual approach to socialism, seeking to build alliances with other social and political groups. The Social Democrats were a broader political group that included both the Bolsheviks and Mensheviks before they split into these two factions. Radicals, while they could encompass various revolutionary groups, do not specifically refer to the Bolsheviks or their distinct ideology. Thus, the term "Bolsheviks" is the one that accurately identifies the key players in the October Revolution.