Helveth , an ancient people of Celtic origin, who in historical times occupied the country between the* Rhine, the lake of Constance, the Rhone, the lake of Geneva, and the Jura; that is, somewhat less than the territory of modern Switzerland (Helvetia). They first appear in history toward the close of the 2d century B. C, when one of their divisions, the so-called pagus Tigurinus, joined the Cimbri on their march to invade Italy, and defeated the Roman consul Lucius Cassius (107). After the defeat of the Cimbri and Teutons by Marius, they retired to their territory, where they numbered 12 towns and 400 villages. They left it again at the time of the first triumvirate, invading Gaul, which had been assigned as a province to Caesar, under the command of Orgeto-rix, one of their chiefs. Caesar routed them at Bibracte (Autun in Burgundy), and the survivors returned beyond the Jura. Numerous Roman castles and colonies were now planted in their land, which was known as Ager Helve-tiorum, until it was attached to Transalpine Gaul. Having refused to acknowledge Vitel-lius as emperor, they were rigorously chastised by his generals. After that the Helvetii almost disappear.

Their territory was occupied by the Alemanni, and in its S. W. part by the Burgundians during the last period of the West Roman empire. (See Switzerland.)