Omurtag 1 was called Mortagon and Moutragon: Theoph. Cont., Zon. King of the Bulgars: Theoph. Cont. II 17 (p. 64) (Μορτάγων ὁ τῶν Βουλγάρων βασιλεὺς), Zon. XV 23. 17 (Μορτάγων ὁ τῶν Βουλγάρων κατάρχων). Successor of Krum: Theoph. Cont. V 4 (p. 217) (Μουτράγων ὁ τοῦ Κρούμου διάδοχος). He made a thirty-year treaty with the emperor Leo V (Leo 15): Theoph. Cont. II 17 (p. 65), Zon. XV 23. 17. During the siege of Constantinople by the rebel Thomas the Slav (Thomas 7), Omurtag 1 sent secret envoys to the emperor Michael II (Michael 10) offering to send military assistance; the offer was declined by Michael 10, but the Bulgar king, allegedly moved partly by the desire for booty and partly by the wish to consolidate the thirty-year treaty formerly agreed with the Romans, nevertheless prepared his army to attack the rebel; he crossed the border and made camp near Kedouktos; there Thomas 7 went to engage him, taking with him the whole of the force which he had led against Constantinople; in the ensuing battle the Bulgars routed Thomas 7's forces and scattered them far and wide and the Bulgar ruler (ὁ τῶν Βουλγάρων ἀρχηγός: Theoph. Cont.) returned home with a large number of captives and a great quantity of booty: Theoph. Cont. II 17-18 (pp. 64-66), Zon. XV 23. 17-20.

Ruler of Boulgaria (Μορτάγων ὁ κύριος Βουλγαρίας); he offered his assistance to Michael 10 against the rebel Thomas 7; Michael 10 declined the offer but they came anyway and defeated Thomas 7 who had withdrawn his troops from the siege of Constantinople to deal with them; this occurred ten years after the making of the Thirty Years Peace between the Bulgars and the emperor Leo 15: Genesius II 7. The date was, perhaps, late 822.

He is said to have had some of the prisoners who had been carried off into captivity at the fall of Adrianople in 813 martyred for their adherence to the Christian faith; among them was the archbishop Manuel and supposedly relatives of Basilios 7 (the future emperor Basil I); perhaps identical with the Bulgar ruler (ὁ τῶν Βουλγάρων ἄρχων) who subsequently allowed the surviving captives to return home when he was no longer able to resist pressure from the Roman forces: Theoph. Cont. V 4 (pp. 216-217), cf. Theod. Stud., Catech. Parva 63 (pp. 220ff., Auvray) (unnamed ruler of the Bulgars who ordered Christian captives to eat meat during Lent and killed those who refused). Elements of this story are hard to reconcile with other data about Omurtag 1 and may be unhistorical.

(Publishable link for this person: )