The so-called Free Dacians (Romanian: Daci liberi) is the name given by some modern historians to those Dacians who putatively remained outside, or emigrated from, the Roman Empire after the emperor Trajan's Dacian Wars (AD 101-6). Dio Cassius named them Dakoi prosoroi (Latin: Daci limitanei) meaning "neighbouring Dacians".A substantial population of Dacians existed on the fringes of the Balkan Roman provinces, especially in the eastern Carpathian Mountains, at least until about AD 340.