 Kiev's dominance waned, to the benefit of Vladimir-Suzdal in the north-east, Novgorod Republic in the north-west and Galicia-Volhynia in the south-west.Ultimately Kievan Rus' disintegrated, with the final blow being the Mongol invasion of 1237–40 that resulted in the destruction of Kiev and the death of about half the population of Rus'.The invading Mongol elite, together with their conquered Turkic subjects (Cumans, Kipchaks, Bulgars), became known as Tatars, forming the state of the Golden Horde, which pillaged the Russian principalities; the Mongols ruled the Cuman-Kipchak confederation and Volga Bulgaria (modern-day southern and central expanses of Russia) for over two centuries.