Map of the Roman province Maxima Sequanorum (c. 300 AD), which comprised the territories of the Helvetii, Sequani and several smaller tribes. The relative locations of the Helvetian pagi Tigurini and Verbigeni, though indicated on the map, remain unknown.
A map of Gaul in the 1st century BC, showing the relative positions of the Celtic tribes.
The Helvetians were subjugated after 52 BC, and under Augustus, Celtic oppida, such as Vindonissa or Basilea, were re-purposed as garrisons. In AD 68, a Helvetian uprising was crushed by Aulus Caecina Alienus.The Swiss plateau was at first incorporated into the Roman province of Gallia Belgica (22 BC), later into Germania Superior (AD 83).The Helvetians, like the rest of Gaul, were largely Romanized by the 2nd century. In the later 3rd century, Roman control over the region waned, and the Swiss plateau was exposed to the invading Alemanni. The Alemanni and Burgundians established permanent settlements in the Swiss plateau in the 5th and 6th centuries, resulting in the early medieval territories of Alemannia (Swabia) and Upper Burgundy.
The endonymHelvetii is mostly derived from a Gaulishelu-, meaning "gain, prosperity" or "multitude", cognate with Welshelw and Old Irish prefix il-, meaning "many" or "multiple"
(from the PIE root*pelh1u- "many").
The second part of the name has sometimes been interpreted as *etu-, "terrain, grassland", thus interpreting the tribal name as "rich in land".
The earliest attestation of the name is found in a graffito on a vessel from Mantua, dated to c. 300 BC. The inscription in Etruscan letters reads eluveitie, which has been interpreted as the Etruscan form of the Celtic elu̯eti̯os ("the Helvetian"), presumably referring to a man of Helvetian descent living in Mantua.