In 1660 Daniel IV was eventually restored to a small portion of his father's estates by Charles II of England, who gave the rest away to Cromwell's soldiers. In 1689 he sat as a member of the House of Commons of the Patriot Parliament of James II, and in the next year, under Governor Sir Edward Scott, was the Deputy Governor of Charles Fort, Kinsale, when besieged by John Churchill, 1st Duke of Marlborough (then 1st Earl). After holding out for ten days, they received guarantees before surrendering, O'Donovan delivered the keys to Marlborough, and they and the 1200 strong garrison were allowed to march out to Limerick. See Siege of Cork.