Complex sentence: With the rise of the 1917 revolution, the Altay attempted to make their region a separate Burkhanist republic called Oyrot, but their support for the Mensheviks during the Civil War led to the venture's collapse after the Bolshevik victory and the rise of Joseph Stalin.
Split into simpler sentences: With the rise of the 1917 revolution, the Altay attempted to make their region a separate Burkhanist republic called Oyrot. Their support for the Mensheviks during the Civil War led to the venture's collapse after the Bolshevik victory and the later rise of Joseph Stalin.