From his father's first marriage to Mary Erskine, he had an elder half-brother, David Melville, 6th Earl of Leven.

[2] In 1775, before the American War of Independence broke out, he led troops to Salem, Massachusetts looking for contraband weapons.

His force was eventually allowed to proceed, but found nothing of consequence, and was received with hostility during the expedition.

[3] In 1780, he was sent to the Chesapeake Bay by Sir Henry Clinton in order to "make a powerful diversion in [Earl Cornwallis's] favor by striking at the magazines then collecting by the enemy ... for supplying the army they were assembling to oppose him.

"[4] He became major general in 1782 and was made Colonel of the 63rd (West Suffolk) Regiment of Foot the same year.