[Ir. Deasmhumhain, Desmuma, South Munster]. A territory in southern Ireland, recognized before the carving out of counties in the 17th century, coextensive today with Co. Kerry and much of Co. Cork and Co. Limerick. In the 16th century Desmond was a theatre of armed resistance to English rule led by the Fitzgerald family or ‘Geraldines’, and has enjoyed rich romantic associations ever since. As the title of earl was in succession for several centuries, many historical figures could be called ‘earl of Desmond’, but the one most celebrated in story is Gerald, also known as Lord Gerald or the Red Earl.
The name Desmond [Ir. Deasmhumhnach] was uncommon in Ireland until modern times, although it had gained some cachet, ironically, in England by the late 19th century; the ModIr. Deasúin appears to be a nationalist retranslation.