WThe Diocese of Africa was a diocese of the later Roman Empire, incorporating the provinces of North Africa, except Mauretania Tingitana. Its seat was at Carthage, and it was subordinate to the Praetorian prefecture of Italy.
WThe Diocese of Asia was a diocese of the later Roman Empire, incorporating the provinces of western Asia Minor and the islands of the eastern Aegean Sea. The diocese was established after the reforms of Diocletian, was subordinate to the Praetorian prefecture of the East, and was abolished during the reforms of Justinian I in 535.
WThe Diocese of Gaul was a diocese of the later Roman Empire, under the praetorian prefecture of Gaul. It encompassed northern and eastern Gaul, that is, modern France north and east of the Loire, including the Low Countries and modern Germany west of the Rhine.
WThe Diocese of Pannonia, from 395 known as the Diocese of Illyricum, was a diocese of the Late Roman Empire. The seat of the vicarius was Sirmium.
WThe Diocese of Pontus was a diocese of the later Roman Empire, incorporating the provinces of northern and northeastern Asia Minor up to the border with the Sassanid Empire in Armenia. The diocese was established after the reforms of Diocletian, and its vicarius, headquartered at Amaseia, was subordinate to the Praetorian prefecture of the East. Its military forces, facing the Sassanid threat, were commanded by the dux Ponti et Armeniae until the middle of the 5th century, and by two separate duces afterwards, until Justinian I instituted a new magister militum per Armeniam for the Armenian frontier. Justinian's reforms also abolished the diocese in 535, and its vicar was made into the governor of Galatia I. The results however were not satisfactory, and the diocese was reestablished in 548, continuing to function until replaced by the themata of Armeniakon and Opsikion in the later 7th century. On the north east shore of the Black Sea, the cities Nitike, Pitiyus, and Dioscurias were part of the diocese until the 7th century. The diocese included 12 provinces: Bithynia, Honorias, Paphlagonia, Helenopontus, Pontus Polemoniacus, Galatia I and Galatia II (Salutaris), Cappadocia I and Cappadocia II, Armenia I, Armenia II, Armenia Maior and the autonomous Armenian principalities (Satrapiae) in the area of Sophene. In 536, Armenia III and Armenia IV were created.
WThe Diocese of the East was a diocese of the later Roman Empire, incorporating the provinces of the western Middle East, between the Mediterranean Sea and Mesopotamia. During late Antiquity, it was one of the major commercial, agricultural, religious and intellectual areas of the empire, and its strategic location facing the Sassanid Empire and the unruly desert tribes gave it exceptional military importance.
WThe Diocese of Thrace was a diocese of the later Roman Empire, incorporating the provinces of the eastern Balkan Peninsula. Philippopolis was the capital.
WEuropa was a Roman province within the Diocese of Thrace.
WThe Diocese of the Seven Provinces, originally called the Diocese of Vienne after the city of Vienna, was a diocese of the later Roman Empire, under the praetorian prefecture of Gaul. It encompassed southern and western Gaul, that is, modern France south and west of the Loire, including Provence.