ULSTER, a province of Ireland occupying the northern part of the island. It includes the counties Donegal, Londonderry, Antrim, Fermanagh, Tyrone, Cavan, Monaghan, Armagh and Down. Ulster ( Uladh) was one of the early provincial kingdoms of Ireland, formed, according to the legendary chronicles, at the Milesian conquest of the island ten centuries before Christ, and given to the descendants of Ir, one of the sons of Mileadh. Interprovincial wars frequently altered its boundaries, notably in 332 when the three Collas, sons of Eochaidh Doimhleln, conquered the land between the river Boyne and Lough Neagh, which became a separate kingdom under the name of Uriel (Oriel or Orgial). Its princes maintained themselves until the close of the 16th century. In 1177 John de Courci, with the countenance of Henry II., set out to the conquest of Ulster. His operations were gradually successful, and he became lord deputy of Ireland in 1186 (see above). The nominal reign of the last king of Ulster closed in 1200. In 1585 Lord Deputy Sir John Perrot undertook the shiring of Ulster (excluding the counties Antrim and Down, which had already taken shape) ; and his work, though of little immediate effect owing to the rising of Hugh O'Neill, served as a basis for the division of the territory at the plantation of Ulster in the reign of James I.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)