Syrmia County was re-established in 1745 as part of the
Kingdom of Slavonia, a
Habsburg province, which was part of both the
Habsburg Kingdom of Croatia and the
Habsburg Kingdom of Hungary. This new county did not cover the whole of its later territory – the southern and furthest eastern parts instead passed to the
Slavonian Military Frontier (and partially to the
Banat Military Frontier 1849–60). The Kingdom of Slavonia was mainly inhabited by Serbs and Croats. In 1848 and 1849, the area of the county was part of the
Serbian Voivodship, a
Serbian autonomous region proclaimed at the May Assembly in
Karlovci. Between 1849 and 1860 the eastern part of the county was part of the
Voivodeship of Serbia and Banat of Temeschwar, a separate crown land of the
Austrian Empire, formally becoming part of the
Neusatz District from 1854; the western part around
Vukovar passed to the Slavonian
Osijek County. After 1860, Syrmia County was established again, and was reincorporated into the Kingdom of Slavonia, which was a completely separate Habsburg province at the time. In 1867, as a consequence of the between the Austrians and the Hungarians, the Kingdom of Slavonia was incorporated into
Transleithania, the half of
Austria-Hungary run from
Budapest, and in the
Hungarian-Croatian Settlement of 1868, it was incorporated into
Croatia-Slavonia, a formally separate kingdom within the
Kingdom of Hungary, which had a certain level of autonomy and was ruled by its own
ban. In 1881 the Slavonian Military Frontier was abolished; the
Petrovaradin district and part of the
Brod district would be merged into Syrmia County by 1886. After
World War I, the area of Syrmia County became part of the newly formed
Kingdom of Serbs, Croats and Slovenes in 1918 and this was confirmed by the
Treaty of Saint-Germain in September 1919. The County of Syrmia was an official administrative division of the
Kingdom of Serbs, Croats and Slovenes between 1918 and 1922, and then was transformed into the Province (Oblast) of Syrmia (de facto it was carried out in 1924). ==Demographics==