Prehistory
Parts of the Baltic region retained large wilderness areas for longer than anywhere else in Europe. In prehistory, the east of the area was inhabited by the Eastern Balts, whilst the Western Balts inhabited the Sambian peninsula and the areas to the west. Over time, the Western Balts consolidated into the Old Prussian nation. The Eastern Balts of the area, including the Curonians, consolidated into (a part of) the Latvian and Lithuanian nations.
About 350 BC Pytheas called the territory Mentenomon and the inhabitants Guttones, neighbors of the Teutones. A river to the east of the Vistula was called the Guttalus (also Guthalus) and was assumed to have been either the Memel, the Alle, or the Pregel.
Read more about this topic: Prussia (region)