When examining the causes of the revolution of 1917 in the Russian Empire, and the course it took, we always face not only social but also national factors. The resolution of national aspirations was intertwined with the social aspirations of the revolution, and we have to admit that national mobilisation would often lose to social mobilisation. This paper shows the interaction between those factors, mainly on the basis of the Ukrainian and Transcaucasian cases, and reveals how the development of events on national peripheries directly affected events at the centre, and vice versa. The social explosion of 1917 that broke out in Imperial Petrograd was echoed by a national mobilisation that forced the centre to make concessions to the peripheries. The subsequent success of the Bolsheviks, and the national disintegration on the peripheries, was affected by the balance created between the unique social project and national factors, as well as the readiness not to block the way to national sovereignty and cultures, provided governance in the national area was arranged in compliance with the Soviet model.