Battle of Sebastopolis

The Battle of Sebastopolis was fought at Sebastopolis in the middle of Armeniac Theme in 692 CE between the Byzantine Empire and the Umayyad Caliphate. The battle ended the peace that had existed between the two powers since 680.

Justinian II sought to restore the glory of the Roman Empire under Justinian I by pursuing aggressive military campaigns that reversed his father's peaceful policies. Early on, he broke a treaty with the Bulgarians and attacked Slavic tribes near Thessaloniki, many of which were transferred to the depopulated Opsician Theme, granting them land and recruiting them to form a new elite military corps. Justinian II also undermined a treaty with the Umayyad caliphate under Abd al-Malik ibn Marwan over tribute payments, breaking the treaty. His Slavic military corps fought the Umayyads at Sebastopolis but deserted en masse, resulting in a Byzantine defeat. Following this, Justinian II harshly punished the surviving troops and their families.