Syrmia (Ekavian Срем or Ijekavian Сријем) is a region of the southern Pannonian Plain, which lies between the Danube and Sava rivers. It is divided between Serbia and Croatia. Most of the region is flat, with the exception of the low Fruška gora mountain stretching along the Danube in its northern part.
The word "Syrmia" is derived from the ancient city of Sirmium (now Sremska Mitrovica). Sirmium was a Celtic or Illyrian town founded in the third century BC.
Srem (Срем) and Srijem are used to designate the region in Serbia and Croatia respectively. Other names for the region include:
Latin: Syrmia or Sirmium
Hungarian: Szerémség, Szerém, or Szerémország
German: Syrmien
Slovak: Sriem
Rusyn: Срим
Romanian: Sirmia
Between 3000 BC and 2400 BC, Syrmia was at the centre of Indo-European Vučedol culture.
Pannonia Secunda and Sirmium
Sirmium was conquered by Romans in the first century BC and became the economic and political capital of Pannonia. In 6 AD, there was an uprising of the indigenous peoples against Roman rule. However, ten later Roman Emperors were born in Sirmium or nearby. They included Herennius Etruscus (227-251), Hostilian (230?-251), Decius Traian (249-251), Claudius II (268-270), Quintillus (270), Aurelian (270-275), Probus (276-282), Maximianus Herculius (285-310), Constantius II (337-361) and Gratian (367-383).
Byzantine Syrmia (567-582) and Battle of Syrmia (1167)
In the 6th century, Syrmia was part of the Byzantine province of Pannonia. During that time, Byzantine rule was challenged by Ostrogoths and Gepids. In 567, Byzantine rule was fully restored, although it later collapsed during the Siege of Sirmium by Avars and Slavs (582). It remained under Avar rule up to c. 800, when it came under the control of the Frankish Empire. In 827, Bulgars invaded Syrmia and continued to rule after a peace treaty in 845 AD. The region was later incorporated into the Principality of Lower Pannonia, but during the 10th century it became a battleground between Hungarians, Bulgarians, and Serbs.