It is generally believed that the Slavs, so numerous in the fifth and sixth centuries, dispersed in many directions and could not all have inhabited the territory of Polesia, the area of the Pripet marshes in present-day Poland, Byelorussia, and the Ukraine, where they used to be located. Even though they may have spread to greater territories, their tribes must have occupied adjacent regions. They, indeed, continued to speak the same language, the "common Slavic'' until their great migratory periods (in the fifth to sixth centuries). \n\nIn the fifth century B.C., a search for the exotic led the Greeks to discover Scythia and some of its mysteries. They perceived in the north of Hellespont Scythian "farmers" who may have been partly the ancestors of the Slavs. Throughout the first centuries, the Romans came in contact (directly or indirectly) with the Slavs along the Oriental border of their Empire, from the North Sea to the Black Sea and from the Germanic territory to Thrace, as they followed the Danube River. \n\n In the middle of the first millennium, the Slavs were called Venedes in their western territory, Sclavenes in the south and Antes in the east. Jordanes was able to locate the Veneti accurately. According to him, their territory formed a vast triangle extending along the eastern side of the Carpathians and beyond. It reached the high Vistula on the north, the Dnieper in the east, and the Prut in the west. He divided them into two main groups and described the numerous groups: the Veneti tribe settled in rather extensive areas starting at the source of the Visla (Vistula). Although their names changed according to tribes and places, they were usually called Sclavenes and Antes. The Sclavenes and the Antes occupied the entire left bank of the Danube in the fifth century from where they expanded into Balkan peninsula. Contrary to other barbaric peoples, Byzantium was never able to push the Slavs out of this area.