Bulgarian lands across the Danube
In Bulgarian historiography, the Bulgarian lands across the Danube, also called Transdanubian Bulgaria (Bulgarian: Отвъддунавска България), refer to territories under the control of the Bulgarian Empire north of the Danube. These territories today cover the territory of Romania and Moldova, eastern Hungary, Vojvodina in Serbia and Budjak in Ukraine.
Source: Wikipedia — Bulgarian lands across the Danube (CC BY-SA 4.0)