The "oppidum" of the Allobroges became a Roman colony about 47 BC under Julius Caesar, but the Allobroges managed to expel them; the exiles then founded the colony of "Lugdunum" (today's Lyon). Ethnarch of Judea Herod Archelaus was exiled here in 6 AD. During the early Empire, Vienna (as the Romans called it—not to be confused with today's Vienna, then known as Vindobona) regained all its former privileges as a Roman colony. In 260 Postumus was proclaimed emperor here of a short-lived Gallo-Roman empire. Later it became a provincial capital of the Dioecesis Viennensis. Vienne became the seat of the vicar of prefects after the creation of regional dioceses, of which the date is still controversial. Regional dioceses were created during the First Tetrarchy, 293–305, or possibly later as some recent studies suggest in 313, but no later than the Verona List, which is securely dated to June 314.