Russian civilization first emerged round the towns of Novgorod and Kiev, where it flourished from the ninth century to the end of the thirteenth. It was during the period of Moscow domination that the exigencies of the long and bitter struggle against barbarian rule brought into being the two characteristic features of Russian political and social life—autocracy and serfdom. European Russia alone was sixteen times larger than Great Britain. Russia's climate is continental, with long cold winters, and short, but hot, summers. The immense plain making up European Russia is interrupted only by the low range of the Urals in the east, the Central Russian elevation, including the Valdai Hills, the Volga elevation, and the lofty range of the Caucasus mountains in the south. Russia stood easily first among the nations of Europe, both as regards the number of her population and the rate at which it increased.