Step 1: Understanding the Concept:
This question pertains to a key event in the history of the Russian Revolution and the formation of the Soviet Union.
Step 2: Detailed Explanation:
\[\begin{array}{rl} \bullet & \text{Under the leadership of Vladimir Lenin, the Bolshevik Party, after seizing power in the October Revolution of 1917, officially changed its name to the Russian Communist Party (Bolsheviks) in March 1918. } \\ \bullet & \text{This name change was significant as it distanced the party from the more moderate social democratic parties of Europe and emphasized its commitment to the principles of communism as laid out by Karl Marx. } \\ \bullet & \text{Leon Trotsky and Joseph Stalin were other prominent Bolshevik leaders, but the decision was made under Lenin's leadership. Otto von Bismarck was a German statesman and is unrelated to Russian politics. } \\ \end{array}\]
Step 3: Final Answer:
Vladimir Lenin was the leader who changed the name of the Bolshevik Party to the Communist Party.