), an important city in the south-eastern part of Lower Pannonia, was an ancient Celtic place of the Taurisci, on the left bank of the Savus, a little below the point where this river is joined by the Bacuntius (Plin. Nat. 3.28
.) Zosimus (2.18) is mistaken when he asserts that Sirmium was surrounded on two sides by a tributary of the Ister.
The town was situated in a most favourable position, where several roads met (It. Ant.
pp. 124, 131; It. Hieros.
p. 563), and during the wars against the Dacians and other Danubian tribes, it became the chief depot of all military stores, and gradually rose to the rank of the chief city in Pannonia. (Herodian, 7.2.) Whether it was ever made a Roman colony is not quite certain, though an inscription is said to exist containing the words Dec. Colon. Sirmiens.
It contained a large manufactory of arms, a spacious forum, an imperial palace, and other public buildings, and was the residence of the admiral of the first Flavian fleet on the Danube. (Amm. Marc. 17.13
; Notit. Imp.
) The emperor Probus was born at Sirmium. (Vopisc. Prob.
3, 21; comp. Strab. ii. p.134
: Ptol. 2.16.8
; Steph. B. sub voce Eutrop. 9.17
; Aethicus, p. 715, ed. Gronov.; Geog. Rav. 4.19.)
The city is mentioned for the last time by Procopius (B. Goth.
3.33, 34), as being in the hands of the Avari, but when and how it perished are questions which history does not answer. Extensive ruins of it are still found about the modern town of Mitrovitz.
(See Orelli, Inscript.
n. 3617; Marsili, Danubius,
p. 246, foll.)