Thurgau, Switzerland

Canton of NE Switzerland, S of the Lake of Constance, with its capital at Frauenfeld. Inhabited since prehistoric times, it appeared first as a political unit in the eighth century a.d. It belonged to the dukes of Zähringen and the counts of Kyburg before passing to the Hapsburgs in 1264. Captured by the confederated Swiss states in 1460, it became a canton of the Helvetic Republic in 1798.