The Bulgar migrations and settlements after the decline of Old Great Bulgaria in the 7th century
Fall of the Old Great Bulgaria (665) and migration of Bulgarians.
The Bulgars were Turkic semi-nomadic warrior tribes that flourished in the Pontic-Caspian steppe and the Volga region during the 5th-7th century.
They became known as nomadic equestrians in the Volga-Ural region, but some researchers believe that their ethnic roots can be traced to Central Asia.
During their westward migration across the Eurasian Steppe, the Bulgar tribes absorbed other tribal groups and cultural influences in a process of ethnogenesis, including Iranic, Finno-Ugric, and Hunnic tribes.
The Bulgars spoke a Turkic language, the Bulgar language of the Oghuric branch. They preserved the military titles, organization, and customs of Eurasian steppes as well as pagan shamanism and belief in the sky deity Tangra.
The Bulgars became semi-sedentary during the 7th century in the Pontic-Caspian steppe, establishing the polity of Old Great Bulgaria c. 630-635, which was defeated by the Khazar Empire in 668 AD.
In 681, Khan Asparukh conquered Scythia Minor, opening access to Moesia, and established the Danubian Bulgaria - the First Bulgarian Empire, where the Bulgars became a political and military elite.
They merged subsequently with established Byzantine populations, as well as with previously settled Slavic tribes, and were eventually Slavicized, thus becoming one of the ancestors of modern Bulgarians.
The remaining Pontic Bulgars migrated in the 7th century to the Volga River, where they founded the Volga Bulgaria; they preserved their identity well into the 13th century.
The modern Volga Tatars, Bashkirs and Chuvash people claim to have originated from the Volga Bulgars.