The village Bolgari near Kanzan, surrounded by numerous graves in which most interesting archaeological finds have been made, occupies the site of one of the cities - perhaps the capital - of that extinct kingdom.
The history, Tarikh Bulgar, said to have been written in the 12th century by an Arabian cadi of the city Bolgari, has not yet been discovered; but the Arabian historians, Ibn Foslan, Ibn Haukal, Abul Hamid Andalusi, Abu Abdallah Harnati, and several others, who had visited the kingdom, beginning with the 10th century, have left descriptions of it.
Their chief town, Bolgari or Velikij Gorod (Great Town) of the Russian annals, was often raided by the Russians.
In the second half of the 15th century Bolgari became part of the Kazan kingdom, lost its commercial and political importance, and was annexed to Russia after the fall of Kazan.
Amongst the nomadic Ugrians and agricultural Slays of the north their frontier fluctuated widely, and in its zenith Khazaria extended from the Dnieper to Bolgari upon the middle Volga, and along the eastern shore of the Caspian to Astarabad.
Bolgari, Nizhniy-Novgorod, Kazan and Vasilsursk have successively been its seat since the 10th century.