Moldovenism is a political term used to refer to the support and promotion of the Moldovan identity and Moldovan culture primarily by the opponents of such ideas. Some of its supporters ascribe this identity to the medieval Principality of Moldavia. Others, in order to explain the current differences between Romanian-speaking inhabitants of the two banks of the Prut River, ascribe it to the long incorporation of Bessarabia in the Russian Empire and the Soviet Union. The opponents, on the contrary, claim that Moldovans and Romanians are a single ethnic group and that the Moldovan identity was artificially created by the USSR.