Rule of Kubrat, or Kurt, of the Dulo tribe, approximately one century after Bulgarian settlement in the Balkans (See 673–78). His dominion extended from the Don to the Caucasus. In 619 he visited Constantinople to secure aid against the Avars, at which time he became converted to Christianity, though this step seems to have had no consequences for his people.
Isperikh (Asperuch), the son of Kurt. The old Great Bulgaria was disrupted by the attacks of Avars and Khazars, and various tribes of Bulgars moved westward into Pannonia and even into Italy. Those under Isperikh crossed the Danube (650–70) and established a capital at Pliska. In 680 they defeated a Byzantine army and occupied the territory between the Danube and the Balkan Mountains. At the same time they still held Wallachia, Moldova, and Bessarabia.
Tervel, to whom Emperor Justinian II paid a subsidy or tribute, but only after the imperial forces had been defeated at Anchialus (708) and after Tervel had advanced to the very gates of Constantinople (712).
Sevar, during whose reign the peace with the empire was maintained. The Dulo dynasty came to an end with Sevar, whose death was followed by an obscure intertribal struggle.
Kormisosh, of the Ukil tribe. Until the very end of his reign he maintained peace with the empire, until further domestic disorders gave the signal for Byzantine attacks (from 755 on).
