CONNAUGHT (kon'acht or kon'awt), a north-western prov ince of Ireland having as the greater part of its eastern boundary the river Shannon, over its middle course. It includes the coun ties Mayo, Sligo, Leitrim, Galway and Roscommon (qq.v. for topography, etc.).
In early times, Connaught (Connachta) was a Firbolg or pre Celtic state, but about A.D. 150 it passed under the Gaelic dynasty which ruled at Cruachu, now Croghan, in Co. Roscommon. This dynasty pushed over the Shannon and founded a new kingdom of Meath, with Tara as its capital about 25o. Connaught and Meath then remained a joint kingdom till 483, when the former became a separate state which lasted till 1224. In the 12th century Connaught produced a great High King in Turloch O'Connor. On the death of Cathal "Crovderg," Henry III. made a grant of Connaught to Richard de Burgh, saving a few cantreds in Co. Roscommon to the O'Connors (1227). Richard's son Walter became earl of Ulster as well as lord of Connaught, but when Earl William was murdered in 1333 his heiress, marrying prince Lionel of Clarence, ultimately carried these titles to the Crown. Connaught was, however, occupied by junior branches of the de Burghs, who took respectively the appellations of Mac William "Uachtair" and "Iochtair" ("the Upper and Lower MacWilliam"), or the Clanrickard and Mayo Burkes. In Ulick Burke was created earl of Clanrickard, and in 1603 "Mac William Iochtair" Viscount Mayo. In 1576 Connaught was divided into shires by Sir Henry Sidney, who also placed it, like Munster, under a president, a system which lasted 7o years. In 1585 Sir John Perrot made with the resident gentry and chiefs the "Com position of Connaught," which confirmed them in their lands by knight-service of the Crown. The result was that the province remained loyal on the whole during the Tyrone rising, and till 164o was the most Gaelic and Norman part of Ireland. Its history is henceforth part of the national history.