1723-93. He was of Scottish descent.
His initial service was as a petty officer aboard the Leopard, 50, Captain Lord Colville, and he was commissioned lieutenant at the relatively old age of 33 on 15 November 1756.
Commanding the Hunter 10 from the spring of 1760, he captured the privateer Revanche on 8 January 1761 and cruised off the coast of Portugal later that year. In September 1762 he joined the squadron sent by Commodore John Moore in the Downs to search a Dutch convoy, one that had to resort to force to fulfil its orders. The Hunter was paid off in April 1763
Ferguson was posted captain on 6 June 1763 and appointed to the Romney 50, flagship to Rear-Admiral Lord Colville who went out as commander-in-chief of the North American station. The Romney was paid off in October 1766.
In December 1775 he was appointed to the dull-sailing Brune 32, going out to North America in the following May and participating in New York campaign from July – October 1776 and the occupation of Rhode Island on 8 December. On 23 March 1777 the Brune escorted a force of five hundred men of the 15th Regiment in an attack on rebel works at Peekskill some fifty miles up the Hudson River, and he later led a detached squadron off the Carolinas in the early summer of 1777. On 19 September he captured the privateer Volunteer, which was one of many prizes taken by his frigate.
Exchanging with Captain William Peere Williams into the far speedier but twenty year-old Venus 36, Captain Ferguson was sent with Commodore William Hotham’s reinforcements to Barbados from New York in November 1778. Prior to the Battle of St. Lucia on 15 December the Venus was detailed to silence an enemy battery during the initial landings. She subsequently captured the American privateer Governor Trumbull on 6 March 1779 after an hour’s engagement and performed excellent service at the Battle of Martinique on 17 April 1780.
From May 1780 Ferguson commanded the Intrepid 64 in the Leeward Islands campaign in succession to the late Captain Henry St. John, capturing the privateer Retaliation on 14 June. He then joined the Terrible 74 in July, sailing with fleet to North America and upon its return to the Leeward Islands being present at the capture of St. Eustatius on 3 February 1781. The Terrible was barely engaged at the action off Martinique on 29 April and shortly afterwards Ferguson resigned the command and returned to England to be temporarily replaced by Captain Richard Bickerton.
He ended the war in command of the recommissioned Egmont 74 from June 1782, serving in the Channel and at the relief of Gibraltar on 18 October. After returning to England the Egmont was placed under orders for the West Indies but in the event the peace arrived beforehand and Ferguson again resigned his command.
After becoming lieutenant-governor of Greenwich Hospital upon the death of Captain Broderick Hartwell in 1784 he retained this position until his own death on 14 February 1793, even though his health had been greatly reduced after suffering a stroke whilst travelling to Scotland in 1786, one that left him paralyzed.
Ferguson was a brave if somewhat eccentric officer who had many tales told about him. Lord Colville helped him progress in his early career and he was most highly regarded by Admiral Lord Howe.