Tuath

Tuath is a Gaelic Irish term that refers to both a people and the territorial unit they inhabited. In early and medieval Ireland, it functioned as the basic political and geographic unit of Gaelic society, combining ethnic, social, and political dimensions. The term comes from Old Irish tuath, meaning "people" or "land of the people," and is cognate with Scottish Gaelic tuath.

A tuath consisted of a defined territory and its inhabitants, governed by a local ruler—often titled rí tuaithe (king of the tuath) or a chieftain—who exercised jurisdiction within the borders of the tuath and owed allegiance to a higher king or overking. The size and boundaries varied, and membership was determined by kinship, tenancy, and customary law. Under Brehon law, the tuath was the organizing unit for landholding, justice, and taxation, with social life anchored in kin groups and local obligation.

Several tuatha could make up a larger political complex, such as a kingdom or province, with interlocking relationships among rulers and dynasties. The tuath persisted into the later Middle Ages but its political prominence declined after Norman and English influence reshaped Irish governance. In modern times the term survives mainly in place-names and in historical and genealogical contexts, where it denotes past tribal territories and the traditional lands of families.

See also: Gaelic Ireland; Brehon law; Kingdoms of Ireland; Irish history.