Dulo clan
The "Chronicle of Fredegar" recorded that during Samo's rebellion in 631AD, 9,000 Bulgars led by Alciocus left Pannonia to modern-day Bavaria where Dagobert I massacred most of them. The remaining 700 joined the Wends. At about the time of Samo's realm, Bulgar leader Kubrat of the Dulo clan led a successful uprising to end Avar authority over the Pannonian Plain, establishing Old Great Bulgaria, or Patria Onoguria, "the homeland of Onogurs". The civil war, possibly a succession struggle in Onoguria between the joint Kutrigur and Utigur forces, raged from 631 to 632. The power of the Avars' Kutrigur forces was shattered and the Avars came under the control of Great Bulgaria. At the same time, according to Constantine VII's work "De Administrando Imperio" (10th century), a group of Croats separated from the White Croats who lived in White Croatia and arrived by their own will, or were called by the Byzantine Emperor Heraclius (610-641), to fight and defeat the Avars after which they eventually organized their own principality in Dalmatia.