Anglo-Irish Protestant who was the leading agent of English royal authority in Ireland during much of the period from the beginning of the English Civil War (English Civil Wars) to the Glorious Revolution (1688–89).

Born into the prominent Butler family, he grew up in England and in 1632 succeeded to the earldom of Ormonde. He began his active career in Ireland in 1633 by offering his services to Lord Deputy Thomas Wentworth (later earl of Strafford). Upon the outbreak of the Roman Catholic rebellion in Ireland in 1641, Ormonde was appointed a lieutenant general in the English army. He defeated the rebels of the Catholic Confederacy at Kilrush, Munster (April 15, 1642), and at New Ross, Leinster (March 18, 1643). Those triumphs, however, did not prevent the confederates from overrunning most of the country. Ormonde's attempts to conclude a peace were blocked by a Catholic faction that advocated complete independence for Ireland. The situation deteriorated further, and in July 1647 Ormonde departed from Ireland, leaving the Protestant cause in the hands of the Parliamentarians, who had defeated King Charles I in the English Civil War.

Returning to Ireland in September 1648, Ormonde concluded a peace with the confederacy (January 1649); he then rallied Protestant Royalists and Catholic confederates in support of Charles II, son and successor of Charles I. For several months most of Ireland was under Ormonde's control. But the Parliamentarian general Oliver Cromwell (Cromwell, Oliver) landed at Dublin in August 1649 and swiftly conquered the country for Parliament. Ormonde fled to Charles II's court-in-exile in Paris in December 1650, and for the next 10 years he was one of Charles's closest advisers.

When Charles II returned to England in the Restoration of 1660, Ormonde, who had urged constitutional rather than military rule, was made commissioner for the treasury and the navy. Appointed lord lieutenant of Ireland in 1662, he made vigorous attempts to encourage Irish commerce and industry. Nevertheless, his enemies at court persuaded Charles to dismiss him in 1669. He was restored to royal favour in 1677 and again appointed lord lieutenant of Ireland. Although he was created a duke in the English peerage in 1682, he was recalled from Ireland in 1684 as a result of new intrigues at Charles's court and because of the determination of James, duke of York, to strengthen his supporters in Ireland.