Brian Boru
The name "Cinnéide" belonged to Brian Boru's father Cennétig mac Lorcáin, King of Thomond, in the tenth century AD. (Brian Boru was an "Ard Rí" or High King of Ireland). The Kennedys did not descend directly from Brian Boru, but from Cinnéide's eldest son Donncuan. Donncuan's son Mahon was the first to call himself "Ó Cinnéide" which is Irish for grandson of "Cinnéide".