Dulo clan
With the demise of Khan Sevar (r.738–753) the ruling Dulo clan died out and the Khanate fell into a long political crisis during which the young country was on the verge of destruction. In just fifteen years seven Khans reigned, and all of them were murdered. The only surviving sources of this period are Byzantine and present only the Byzantine point of view of the ensuing political turmoil in Bulgaria. They describe two factions struggling for powerone that sought peaceful relations with the Empire, which was dominant until 755, and one that favoured war. These sources present the relations with the Byzantine Empire as the main issue in this internal struggle and do not mention the other reasons, which could have been more important for the Bulgarian elite. It is likely that the relationship between the politically dominant Bulgars and the more numerous Slavs was the main issue behind the struggle but there is no evidence about the aims of the rival factions. Zlatarski speculates that the old Bulgar military aristocracy was leaning towards war while other Bulgars supported by the majority of the Slavs were inclined for peace with Byzantium.