Túath (plural túatha) is the Old Irish term for the basic political and jurisdictional unit of Gaelic Ireland. Túath can refer to both a geographical territory as well the people who lived in that territory. The smallest túath controlled by a king was about the size of a later Irish barony (about 177sq miles) and kings with greater power would have two or more túatha under their control, according to A Smaller Social History of Ancient Ireland.

Social structure