Duchy of Syrmia

Syrmia (Serbian: Срем / Srem, Croatian: Srijem) is a fertile region of the Pannonian Plain in Europe, which lies between the Danube and Sava rivers. The majority of Syrmia is located in the Srem and South Bačka districts of the Autonomous Province of Vojvodina in Serbia. A smaller area around Novi Beograd, Zemun, and Surčin belongs to the City of Belgrade. The remaining part of Syrmia is divided between multiple municipalities in Serbia and Vukovar-Srijem County in Croatia.

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 in Serbian (Serbian Cyrillic: Срем) and Srijem in Croatian are used to designate the region. Other names for the region include:

Over centuries, Syrmia has been ruled by many different entities. These include the Roman Empire, the Hun Empire, the Ostrogothic Kingdom, the Gepid Kingdom, the Lombard state, the Byzantine Empire, the Avar Khaganate, the Frankish Empire, the Bulgarian Empire, Pannonian Croatia, the Kingdom of Hungary, the Ottoman Empire, the Habsburg Monarchy, the Austrian Empire, Austria-Hungary, the State of Slovenes, Croats and Serbs, the Kingdom of Serbia, the Kingdom of Serbs, Croats and Slovenes, the Kingdom of Yugoslavia, and the Socialist Federal Republic of Yugoslavia. In 1945, on the advice of the Ðilas Commission, the Socialist Federal Republic of Yugoslavia assigned the eastern part of Syrmia to the People's Republic of Serbia and the western part to the People's Republic of Croatia. The westernmost part of Syrmia is in eastern Croatia in Vukovar-Srijem, while the majority of Syrmia is part of Republic of Serbia.

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