In Irish, Kennedy is Ó Cinnéide which means ugly headed or rough-headed. The original holder of the Kennedy name was a nephew of the Irish king Brian Boru, who defeated the Norsemen at the Battle of Clontarf in 1014 and was then killed himself. The ancestral homeland of the Kennedys is in north Tipperary, east Clare and down into south Wexford.

Of all the Kennedys, John F. Kennedy (1917-1963), President of the United States, was the most famous. He was able to trace his direct ancestry back to Co. Wexford. The Kennedy homestead at Dunganstown, near New Ross, can still be visited, while the nearby Kennedy Memorial Park was created in his memory after he was assassinated in Dallas in 1963, just five months after his triumphant visit to Ireland.

Jimmy Kennedy (1902-1984) from Omagh, Co. Tyrone, was a world-famous songwriter. He composed such songs as "Red Sails in the Sunset," inspired by a sunset over Portstewart strand in Co. Antrim, and "Teddy Bear's Picnic."