The prefecture was established in the division of the Empire after the death of
Constantine the Great in 337, and was made up of
dioceses. Initially these were the
Diocese of Africa, the
Diocese of Italy, the
Diocese of Pannonia, the
Diocese of Dacia and the
Diocese of Macedonia (the last two were until united in the
Diocese of Moesia). Eventually the Diocese of Italy was split in two, the
Diocese of Suburbicarian Italy (
Italia suburbicaria: "Italy under the City", also referred to as "Diocese of the City of Rome") and the
Diocese of Annonarian Italy (
Italia annonaria: "provisioning Italy"). In 347, the
praetorian prefecture of Illyricum was established, comprising the dioceses of Pannonia, Dacia and Macedonia. Vulcacius Rufinus was the prefect, 347–352. The new prefecture was abolished in 361 by
Julian and reestablished in 375 by
Gratian. Its territory was contested between the two halves of the Empire, until the final partition in 395, when the
Diocese of Pannonia was split off from the Illyricum and joined to the Western Empire and the prefecture of Italy as the
Diocese of Illyricum. Despite the end of the Western Empire in 476, the Germanic successor states under
Odoacer and
Theodoric continued to use the Roman administrative machinery, as well as being nominal subjects of the
Eastern emperor at
Constantinople. The Prefecture thus survived, but with reduced territorial jurisdiction, confined to regions under Odoacer's or Ostrogothic rule. , before the Lombard invasion in 568 During the
Gothic War (535–554), entire Italy came under the
Byzantine rule, and the Praetorian prefecture of Italy continued to exist, centered in Ravenna, and divided into provinces. However, with the
Lombard invasion in 568, Byzantine rule became reduced to fragmented and increasingly isolated territories. Responding to that, remaining territories were grouped into several regions, or
eparchies in 580 (Aemilia, Annonaria, Calabria, Campania, Urbicaria), but already by 584 the entire administrative structure was reorganized into the
Exarchate of Italy, also centered in Ravenna, and headed by an imperial
exarch of Italy, who was both civilian and military governor of
Byzantine Italy. Within the newly established Italian exarchate, praetorian prefects of Italy continue however to be attested, as heads of civilian branch of administration, until well into the 7th century. One of the last attested holders occurs in 639, and a couple of seals bearing the title
eparchos ("prefect" in Greek) survive from the late 7th century, although it has been suggested that they are a misprint for
exarchos ("
exarch"). == List of known
praefecti praetorio Italiae et Africae ==