Admiral.

Entered Royal Academy, Portsmouth, 1733; served on the Dreadnought, Shoreham, Dragon, and Dauphin; lieutenant, 1740; the Buckingham, 1741; Battle at Toulon (but the Buckingham remained in reserve), 1743; witness at court-martial (1743?), accused of being a mouth-piece for his captain:

`I never ask any man's opinion but go by my own. I always judged Mr. Lestock's conduct on that day unlike an officer, and always said so.'

To flagship Namur, given command of Hinchinbroke, 1744; command of Ambuscade (40 guns), 1747; in Anson's fleet at Battle of Cape Finisterre, 1747; various commands; as commander of Monarque in charge of the execution of Admiral Byng by firing-squad on the quarter-deck, 1757; and at destruction of De la Clue's squadron off Cartagena, 1758; a number of commands; with Hawke at Bay of Biscay, 1760;

Rear-admiral, 1770; commander-in-chief, on the North America station, 1771-1774; (the DNB: "defined as `from the River St. Lawrence to Cape Florida and the Bahama Islands'"); vice-admiral, 1776; commander-in-chief at Newfoundland, primarily fighting American privateers, also seized islands of Saint Pierre and Miquelon, 1776-1779; admiral of the blue, 1782; commander-in-chief, Portsmouth, 1783-1786.

Until 1749 wrote his name as Mountagu.

Sources:
[DNB].

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