Banat (bäˈnät) [key], region extending across W Romania, NE Serbia, and S Hungary. The term banat originally referred to any of several frontier provinces of Hungary and Croatia that were ruled by bans (governors). The Banat region is bordered on the E by Transylvania and Walachia, on the W by the Tisza River, on the N by the Mureşul River, and on the S by the Danube. Except for some eastern mountains, it is primarily an agricultural area of fertile, rolling plains. Inhabited since prehistoric times, the Banat was occupied successively by Romans, Goths, Gepidae, Huns, and Avars. Slavs began to settle there in the 5th cent. and Magyars in the 9th cent. In 1233, King Andrew II of Hungary established the Banat of Severin, a frontier province whose defense was entrusted to the Knights Hospitalers. In the aftermath of the Turkish victory over the Serbs at Kosovo Field (1389) and the Turkish occupation of Serbia (1459), many Serbs emigrated to the Banat, which itself became a Turkish sanjak (province) around 1552. By the Treaty of Passarowitz (1718), the Banat was made an Austrian military frontier zone known as the Banat of Temesvar. Empress Maria Theresa put the region under civilian government in 1751 and brought in thousands of German colonists. In 1779 the Banat passed to Hungary, to which it belonged until 1918, except for a brief period as an Austrian crownland. Although the Allies in World War I had promised through a secret agreement to give the Banat to Romania, it was divided by the Treaty of Trianon (1920) between Romania and newly independent Yugoslavia, with the Szeged district reserved for Hungary.