Union Mordovia earth with Russian land

Inclusion of Mordovia (Mordovia land "Russian Chronicles) in the orbit of the Russian state in its various forms (Kievan Rus, a number of Russian principalities in the period of feudal fragmentation, Moscow Russia, as the centralized Russian state, Russia) did not happen overnight. It was a process that lasted for centuries, in which we can distinguish three main stages: 1) began 1000 years ago, and it can be called Kiev (X-XII cc.), 2) Vladimir-Nizhny Novgorod, Ryazan-Moscow (XIII-XV centuries.) 3) Moscow (XVI century)..