DESMOND (Des-Mumha), an ancient territorial division of Ireland, covering the eastern part of the modern Co. Kerry and the western part of Co. Cork. Its creation as a kingdom is placed in the year 248, when Oliol Olum, king of Munster, divided his territory between his two sons, giving Desmond to Eoghan, and Thomond or North Munster to Cormac. In 1329 Maurice Fitzthomas or Fitzgerald (d. 1356), lord of Decies and Desmond, was created 1st earl of Desmond by Edward III.; like other earls created about that time he ruled his territory as a palatinate, and his family acquired enormous powers and a large measure of independence. Meanwhile native kings continued to reign in a restricted territory until 1596. In 1583 came the attainder of Gerald Fitzgerald, 15th earl of Desmond (q.v.), and in 1586 an act of parliament declared the forfeiture of the Desmond estates to the crown. In 1571 a commission provided for the formation of Desmond into a county, and it was regarded as such for a few years, but by the beginning of the 17th century it was joined to Co. Kerry.
In 1619 the title of earl of Desmond was conferred on Richard Preston, Lord Dingwall, at whose death in 1628 it again became extinct. It was then bestowed on George Feilding, second son of William, earl of Denbigh, who had held the reversion of the earldom from 1622. His son William Feilding succeeded as earl of Denbigh in 1675, and thenceforward the title of Desmond was held in conjunction with that honour.