Henry FitzRoy, 1st Duke of Grafton, (28 September 16639 October 1690) was an illegitimate son of King Charles II of England and his mistress Barbara Villiers. A military commander, Henry FitzRoy was appointed colonel of the Grenadier Guards in 1681 and Vice-Admiral of England from 1682 to 1689. He was killed in the storming of Cork during the Williamite–Jacobite War in 1690.