Exarchates

Exarchates were large administrative and military districts in the late Roman and early Byzantine Empire. An exarchate was headed by an exarch, an official granted both civil authority and provincial military command, appointed by the emperor. The arrangement aimed to strengthen frontier governance and rapid response to threats by combining taxation, administration, and defense under a single ruler. The term is most closely associated with reforms attributed to Maurice and remained in use, with varying importance, into the 7th and 8th centuries. Exarchs often enjoyed substantial autonomy within their territories, acting as imperial representatives with broad jurisdiction over local officials, finances, and troops. Capitals were typically major cities that anchored imperial presence, such as Ravenna in the Italian exarchate and Carthage in the African exarchate. Some historians also refer to an exarchate in Illyricum (the Balkan region), though its boundaries and existence are debated.

The Exarchate of Ravenna was established in the late 6th century to secure Italy against Lombard expansion and to project imperial authority in the western provinces. Its domain included the Italian peninsula and sometimes nearby islands, with Ravenna as the administrative center and liaison to the Papacy. The exarchate endured until the Lombard conquest and the loss of Ravenna in 751, after which Byzantine civil and military authority in Italy waned.

The Exarchate of Africa, created under Heraclius in the mid-7th century, covered Byzantine North Africa, roughly the region of modern Tunisia and parts of the central Maghreb, with Carthage as its capital. It faced the rapid advance of Arab forces and dwindled through the late 7th century, eventually disappearing as a distinct administrative unit.

Over time, the exarchate system declined as the Byzantine Empire adopted the theme system and other administrative shifts, though the term remains a key concept in studies of late antique and early medieval governance.