The Danube defined the region to the north, with the Carpathian Mountains to the north and east. These provinces were important to the Imperial economy as mining regions, and their general significance in the Empire of the 3rd century is indicated by the emperors who came from the region.
The Danube demarcated the northern boundary, with the Carpathian Mountains to the north and east. These provinces were vital for the Imperial economy because they contained mining regions, and their significance in the Empire of the 3rd century is reflected by emperors hailing from this area.