Some scholars have asserted that Dacian was the main language of the sedentary population of the Hungarian Plain, at least as far as the river Tisza, and possibly as far as the Danube. Statements by ancient authors such as Caesar, Strabo and Pliny the Elder have been controversially interpreted as supporting this view, but these are too vague or ambiguous to be of much geographical value. There is little hard evidence to support the thesis of a large ethnic-Dacian population on the Plain: