Switzerland in the Roman era after which the area began to be occupied by Germanic peoples. The Swiss plateau, within the natural borders of the Alps to the South and East, Lake Geneva and the Rhône to the west and the Rhine to the north, was recognized as a contiguous territory by Julius Caesar. This area had been dominated by the La Tène culture since the 5th century BC, settled by a mostly Celtic population (Gauls), of which the Helvetii were the most numerous, but which also included the Rauraci in north-west Switzerland centered on Basel, and the Allobroges around Geneva. South of the Swiss
Inn (river) at the Reschen Pass, since the 16th century at the latest the origin has been seen uniformly in the area of the lakes at the Maloja Pass. There may be a connection between the name Inn and the name of the French river Ain. The source is located in the Swiss Alps, west of St. Moritz in the Engadine region, which is named after the river (Romansh "Engiadina"; Latin "vallis Eniatina"). Shortly after it leaves its source, the Inn flows through the largest lakes on its course, Lake Sils and Lake Silvaplana. It runs north-eastwards, entering Austria, and from Landeck