Under the administrative reforms of Diocletian (r. 284–305), Thracia's territory was divided into four smaller provinces: Thracia, Haemimontus, Rhodope and Europa. The new province of Thracia comprised the northwestern portion of the old province, i.e. the upper valley of the Hebrus river between Haemus and Rhodope and including Philippopolis (in Thracia), which had become the provincial capital in the early 3rd century. It was headed by a governor with the rank of consularis. The four Thracian provinces, along with the two provinces of Moesia Inferior, were grouped into the diocese of Thraciae, which in turn was part of the Prefecture of the East. Militarily, the entire region was under the control of the magister militum per Thracias''. See also Constantinople List of Roman governors of Thracia Thraco-Roman References Sources External links Map of the Roman state according to the Compilation notitia dignitatum Place-names in the Compilation notitia dignitatum Late Roman provinces Greece in the Roman era 40s establishments in the Roman Empire States and territories established in the 40s