Carthy

The MacCarthys (Irish Mac Cárthaigh) were a Gaelic Irish dynasty of Munster whose chiefs ruled the kingdom of Desmond across much of Cork and Kerry. They descended from Carthach, a king of the Eóganacht Chaisil who died in 1045; his grandsons adopted Mac Carthaigh as a surname after their father Muireadhach died in 1092.

After the treaty of Glanmire of 1118 split Munster into Desmond and Thomond, Tadhg Mac Carthaigh became the first king of Desmond. Four septs grew up under him, including the Muskerry MacCarthys, whose Blarney Castle was rebuilt in 1446.

Fineen MacCarthy defeated the Geraldines in 1261, and the septs kept resisting Norman and English encroachment for centuries. The kingdom of Desmond was dissolved in 1596, and the Muskerry branch lost its titles after backing James II in the Williamite War, when it was attainted in 1691.