Late George III period portrait of an infantry officer

A charmingly naive portrait of an officer in a scarlet coatee, circa 1800. oil on canvas, measuring 340 x 29 mm [ 14 x 11 ins approx ]. It is unsigned and there is no information on the sitter. The officer, bust length, wears a gorget and oval shoulder belt plate, both of which have the cypher GR. The gorget finally went out of use by the end of George IV’s reign. The buttons are rather well painted and show a star of St Andrew’s design which would suggest a Scottish regiment. The Black Watch wore a button based on St Andrew’s star. He could well be a member of one of the many Volunteer units which proliferated around the time of the Revolutionary and Napoleonic Wars when invasion was feared. The frame is of a style that was common in the late 18th century and Regency periods but it is probably of later construction.