The Great Khan Kubrat (Kurt), of the Dulo clan, leads a successful uprising to end Avar authority over the Pannonian Plain, establishing what the imperial Greeks will call Old Great Bulgaria, roughgly contemporaneous with Samo's realm.

Kubrat's rule stretches from the Danube Delta to the Volga River.

The civil war, possibly a succession struggle in Onoguria between the joint Avar/Kutrigur Bulgar parties and Kubrat's Utigur Bulgar forces, rages from 631-632.

The power of the Avar/Kutrigur forces is shattered, and the Avars come under the control of "Patria Onoguria" ("the homeland of Onogurs"), or Old Great Bulgaria.

Chronicler Fredegarius recorded that nine thousand Bulgars sought asylum and fled to Bavaria, only to be slaughtered by King Dagobert I of the Franks.