The diocese was established after the reforms of Diocletian and Constantine I in ca. 314. In the early 5th century, the Rhine frontier was breached, and much of Gaul lost to barbarian tribes. The only territory remaining in Roman hands after the 450s was in the northwest, the so-called "Domain of Soissons". After its fall to the Franks in 486 and the end of Roman administration in northern Gaul, the diocese can be said to have de facto ended.
Provincial administration reformed by Diocletian, ca. 293. Praetorian Prefectures established after the death of Constantine I. Empire permanently partitioned after 395. Exarchates of Ravenna and Africa established after 584. Provinces replaced by Theme system, ca. 680.
* affected (boundaries modified/abolished/renamed) by Justinian's administrative reorganization in 534-536 † re-established after reconquest by the Eastern Empire in 534, as the separate praetorian prefecture of Africa