Which faction of the Marxist Russian Social Democratic Labour Party did Nikolai Krivoruchko join?
Nikolai Krivoruchko:  He fought in the Imperial Russian Army in World War I before going over to the Bolsheviks during the subsequent civil war. Bolsheviks: The Bolsheviks, originally also Bolshevists or Bolsheviki (Russian: большевики, большевик (singular) ; ] ; derived from большинство "bol'shinstvo", "majority", literally meaning "one of the majority") were a faction of the Marxist Russian Social Democratic Labour Party (RSDLP) which split apart from the Menshevik faction at the Second Party Congress in 1903.
Bolsheviks