Byzantine Thematic System

Timeline

1. c. 650–700Asia Minor · AnatoliaUnder pressure from the Persian and Arab wars, Emperor Heraclius reorganized the provinces into themes, with military commanders governing garrison troops and collecting military provisions, creating a combined military-civilian model of local rule.
2. c. 780–850Eastern frontier of the Byzantine Empire · Byzantine EmpireDuring the Isaurian dynasty the number of themes increased and the frontier defense system was strengthened; the authority and garrison obligations of theme commanders (strategos) were further institutionalized, making them the backbone of the empire's defense against Arab attacks.
3. c. 1171–1180Constantinople and the Anatolian themes · ConstantinopleThe Komnenian emperors relied on kinsmen generals, the Varangian Guard, and pronoia land grants; the garrison and taxation functions of the themes were weakened, but the thematic names and frontier-defense framework still supported the empire's control of western Anatolia.