Old Great Bulgaria (Medieval Greek: Παλαιά Μεγάλη Βουλγαρία, Palaiá Megálē Voulgaría), also often known by the Latin names Magna Bulgaria[5] and Patria Onoguria ("Onogur land"),[6] was a 7th-century Turkic nomadic empire formed by the Onogur-Bulgars on the western Pontic–Caspian steppe (modern southern Ukraine and southwest Russia).

During the late 7th century, however, an Avar-Slavic alliance in the west, and Khazars in the east, defeated the Bulgars, and Great Bulgaria disintegrated.

The etymology of the ethnonym Bulgar is not completely understood; it is difficult to trace the name back earlier than the 4th century AD.

Variations of the name include Onoguri, Onoghuri, Onghur, Ongur, Onghuri, Onguri, Onogundur, Unogundur, and Unokundur.

Between 630 and 635, Khan Kubrat managed to unite the Onogur Bulgars with the tribes of the Kutrigurs and Utigurs under a single rule, creating a powerful confederation which was referred to by the medieval authors in Western Europe as Old Great Bulgaria,[17] or Patria Onoguria.

[2][20] Kubrat quickly managed to overthrow Avar domination, extending Onogur influence among the Bulgars in Pannonia in what became known as Hungary.

[17] In the times of Emperor Constantine IV, he narrates, Kubrat died and Batbayan, the eldest of his five sons, was left in charge of the state.

Under strong Khazar pressure, Kubrat's other sons disregarded their father's advice to stay together in order to resist the enemies and soon departed, taking their own tribes.

Kuber ruled in Sirmium over a mixed group of peoples – Bulgars, Byzantine subjects, Slavs, and Germanic tribes – as a vassal of the Avar Khagan.

Paul the Deacon in his Historia Langobardorum writing after the year 787 says that in his time Bulgars still inhabited the area, and that even though they speak "Latin", "they have not forsaken the use of their own tongue".

[27] After the state disintegrated under the Khazar attack in 668, Asparukh parted ways with his brothers and led some of the Bulgars to seek a secure home.