The First Arab Siege of Constantinople
By Marek Jankowiak
Travaux et Mémoires, Vol. 17 (2013)
Introduction: No handbook of Byzantine history fails to mention the first Arab siege of Constantinople, a symbolic event that marks the turning of the tide in the first wave of Arab conquests. Usually thought to have lasted four years, from around 674 to 678, it has assumed in the eyes of Byzantinists an epochal significance. After 40 years of continuous defeats by victorious armies of Islam, the successful defence of the city of Constantine saved in extremis the Empire and, for some scholars, the European civilisation. To Georgije Ostrogorsky, “the significance of the Byzantine victory of 678 cannot be overestimated. For the first time the Arab advance was really checked and the invasion which had swept forward as irresistibly as an avalanche was now halted. In the defence of Europe against the Arab onslaught this triumph of Constantine IV was a turning point of world-wide historical importance. […] The fact that it [Constantinople] held saved not only the Byzantine Empire, but the whole of the European civilization.”
Few historians would employ today the same language, but the narrative has been universally accepted in Western historiography. The details of the siege remain, however, shrouded in mystery: its exact dates (670–7 or 674–8?) and length (4 or 7 years?) are a matter of controversy; it is disputed whether the Arabs subjected Constantinople to a regular siege or only to a naval blockade; and the overall logic of events is far from clear.
These problems can be traced back to the single source upon which the modern accounts of the siege are based, the Chronicle of Theophanes the Confessor. His narrative is beset by internal contradictions which, as I will try to show, result from Theophanes’ daring, but unsuccessful attempt at reconciling two sources he had at his disposal. I will argue that these contradictions cannot be satisfactorily solved. However, when considered separately, Theophanes’ two sources tell a consistent story of the Byzantine-Arab warfare in the 660s and 670s, arguably the most obscure decades in Byzantine history. In the second part of this paper, we will see that the picture emerging from their reappraisal is confirmed by independent sources—Greek, Latin, Syriac, and Arabic. All these accounts are, unfortunately, fragmentary, but even though none of them tells the full story of the first Arab siege of Constantinople, they all speak of important events that took place around the year 668. We will see that the early Islamic historical tradition, insofar as it can be accessed in a form preceding its classical codification by historians such as al-Ṭabarī, preserves a trustworthy account of the events. But the key to solving the riddle of the first Arab siege of Constantinople is offered by a contemporary and hitherto unnoticed Byzantine text with which it is fitting to start.