Dictionary of National Biography, 1885-1900/Caulfeild, William (d.1671)
CAULFEILD, WILLIAM, fifth Baron and first Viscount Charlemont (d. 1671), third son of Sir William Caulfeild, second baron, and brother of Toby, third baron [q. v.], succeeded his brother Robert in the title and estates in 1642. He caused the apprehension of Sir Phelim O'Neill, who was chargeable with the murder of Toby, third baron, and had him executed. After the Restoration he was chosen a member of the privy council, and in 1661 he was nominated one of the lords to prepare a declaration requiring conformity to episcopacy. He was named constable and governor of the fort of Charlemont for life, but on 13 April 1664 sold it to the crown for 3,500l. By Charles II he was in 1665 advanced to the degree of viscount. He died in April 1671, and was buried in the cathedral church of Armagh, where there is an elaborate monument to his memory.
[Lodge's Irish Peerage (edit. 1789), iii. 142–6.]