David, 1st Earl of Barrymore (1604-1642) was born on the 10th March 1604 and succeeded to the Barrymore Estates on the 10 April 1617 upon the death of his grandfather, David Barry, 5th Viscount Barry.
He was created Earl of Barrymore on 28 February 1627 and married He married Lady Alice Boyle (1607-1667) in 1631, the second child of Richard Boyle, 1st Earl of Cork (1566-1643) and his second wife Catherine Fenton. This was a significant alliance for the young David Barry, as the Earl of Cork was a powerful man who had acquired much of Waterford and a great deal of Cork, as far as Bandon in the west, as well as purchasing Sir Walter Raleigh's 42,000 acre estate at Lismore during the latter's imprisonment in 1603.
During the 1641 rebellion Barrymore sided with the English and stormed his great-aunt's castle, that of Ballymacpatrick (now Careysville) near Fermoy. He led a regiment at the Battle of Liscarroll and subsequently died of his injuries in the September of 1642. He was buried in Boyle Vault, Youghal, County Cork, Ireland.