In 829, as the young Theophilos (reigned 829–842) ascended the Byzantine throne, the Byzantine–Arab Wars had gone on and off for almost two centuries. An ambitious man and a convinced iconoclast, Theophilos sought to bolster his regime and support his religious policies by military success against the Abbasid Caliphate, the Empire's major antagonist. Throughout the 830s, Theophilos launched a series of moderately successful campaigns against the Caliphate, allowing him to portray himself in the traditional Roman way as a victorious emperor. In 837, Theophilos himself led a major campaign to the region of the upper Euphrates, sacking the cities of Arsamosata and Sozopetra – which some sources claim as Abbasid Caliph al-Mu'tasim (reigned 833–842) own birthplace – and forcing Melitene to pay