The Battle of the Tisza

Khan Omurtag, son of Khan Krum, pursued peaceful policies during his reign and concentrated on strengthening internal authority in Bulgaria. This was necessary because of all the new lands incorporated under Kan Krum. In 827, he was forced into military conflict with the Frankish Empire to recover the Slavic tribes that had broken away from Bulgaria along the Timok, Danube, Tisza and Sava rivers.

King Louis of Bavaria initially repelled Omurtag's troops, but in 529 Omurtag restored the tribes to Bulgaria through military action along the Tisza Valley.