Throughout Russian history famines, droughts and crop failures occurred on the territory of Russia, the Russian Empire and the USSR on more or less regular basis. From the beginning of the 11th to the end of the 16th century, on the territory of Russia for every century there were 8 crop failures, which were repeated every 13 years, sometimes causing prolonged famine in a significant territory. The causes of famine were different, from natural and economic and political crises; for example, the Great Famine of 1931–1933, colloquially called the Holodomor, the cause of which was, among other factors, the collectivization policy in the USSR, which affected the territory of the Volga region in Russia, Ukraine and Kazakhstan.