It is likely that a part of the Vlachs can trace their ancient roots to this region. The present geographic location of the Vlachs is near a former location in the medieval Second Bulgarian Empire (also called the Empire of Vlachs and Bulgars) of the Asens, suggesting their continuity in the area. In addition a Vlach population in the regions around Braničevo (near the ancient Roman city of Viminacium) is attested by 15th century Ottoman defters (tax records). The modern Vlachs occupy the same area where in antiquity the Romans had a strong presence for many centuries: Viminacium and Felix Romuliana.