William Cayley – according to some records, George William Cayley – was the fourth son of the fourth Cayley baronet, Sir George Cayley (1707-91). William was christened at the church of St Michael le Belfrey, York on 5 May 1742.
Like many younger sons of gentry of his day, he embarked on a career in the armed forces, becoming a lieutenant in the British navy in 1762. Promotion came during the War of American Independence. In 1781 he was made a Commander, and from February that year to the end of April 1782 he was captain of the Harpy. On 1 May 1782 he was promoted to Captain and assigned the 74-gun Edgar. On 20 October 1782 he and his ship fought in the Battle of Cape Spartel, off Morocco. The Edgar was part of a fleet under Admiral Howe sent to escort supplies to Gibraltar, which was besieged by a Franco-Spanish fleet. Howe’s fleet evaded the enemy and the much-needed supplies safely reached Gibraltar on 17 October. But three days later battle was joined. The British inflicted significant damage on the enemy, and suffered little themselves. Howe’s orders were so far as possible to avoid combat and to return to Britain as quickly as he could, so his fleet retreated in good order, and the engagement was indecisive. He had achieved his aims.
William Cayley went on to serve in the British navy in the 1790’s, in the wars against France. In 1794 he briefly captained the newly commissioned HMS Unicorn. For a few months in 1795 he captained the Juste, an 80-gun ship captured from the French the previous year. From December 1795 he was captain of the 74-gun Invincible. Over the next few years he escorted convoys across the Atlantic, and also took part in a number of battles. In May 1796 he captured the Alexandre off Madeira, and freed the British Montcalm which that ship had previously captured. The following year the Invincible was part of the fleet which captured Trinidad. In August 1799 William Cayley was present at the surrender of Surinam to the British.
He died at Chatham, Kent, on 3 January 1801.