Complex sentence: He returned to Armenia to become Chairman of the Parliament on November 4,1920 and being arrested after the Bolsheviks came to power in December 1920, but was liberated by the February 1921 revolt against the Soviet regime.
Split into simpler sentences: He returned to Armenia to become Chairman of the Parliament on November 4,1920. Kajaznuni was arrested after the Bolsheviks came to power in December 1920 and was liberated by the February 1921 revolt against the Soviet regime.