Dermot Mac Murragh was the last Irish King of Leinster. He attained the throne in 1140. Having carried off the wife of O'Ruarc, prince of Leitrim, he was attacked by the latter, and after a contest of some years driven out of Ireland in 1167. He then did homage to the English king, and with the help of Richard, earl of Pembroke, recovered his kingdom in 1170, but died in the same year, and was succeeded by Pembroke, who had married his daughter. Research Dermot Mac Murragh
The family of Fitzgerald was an Irish family descended from William, Castellan of Windsor in William the Conqueror's reign. Two branches of this house, the Earls of Desmond and Kildare, were for a long while the practical rulers of the English part of Ireland. The Kildare branch is still represented by the ducal house of Leinster. Research Fitzgerald
The Leinster Regiment was a British infantry regiment formed of the merger of the 100th Regiment of Foot and the 109th Regiment of Foot Research Leinster Regiment