From the Wikipedia page 
The Chuvash Republic (Russian: Чува́шская Респу́блика — Чува́шия, Chuvashskaya Respublika — Chuvashiya; Chuvash: Чăваш Республики, Čăvaš Respubliki), or Chuvashia (Russian: Чува́шия Chuvashiya; Chuvash: Чăваш Ен, Čăvaš Jen) for short, is a federal subject of Russia (a republic). It is the homeland of the Chuvash people, a Turkic ethnic group. Its capital is the city of Cheboksary.
The Chuvash Republic is located in the center of European Russia, in the heart of the Volga-Vyatka economic region, mostly to the west of the Volga River, in the Volga Upland. It borders with the Mari El Republic in the north, Nizhny Novgorod Oblast in the west, the Republic of Mordovia in the southwest, Ulyanovsk Oblast in the south, and the Republic of Tatarstan in the east and southeast.