Sirmium
Sirmium
(sûr`mēəm), ancient city of PannoniaPannonia, ancient Roman province, central Europe, southwest of the Danube, including parts of modern Austria, Hungary, Slovenia, Croatia, and Serbia. Its natives, the warlike Pannonians, were Illyrians. Their final subjugation by Rome took place in A.D. 9.
..... Click the link for more information. . The site is near modern Sremska Mitrovica, NW Serbia. Sirmium was unimportant until occupied late in the 1st cent. B.C. by the Romans in the conquest of Pannonia. It was prominent later, especially in the 3d and 4th cent. A.D., and became the chief city of Lower Pannonia.