His great friend, Douglas, Duke of Hamilton, was seized by a passing fit of military enthusiasm, a few months after John Moore had joined the 51st, which in a letter at that date he described as "one of the best regiments in the service; as to officers, I never knew such a number of fine gentlemanly lads. General Murray told me he did not believe there was such a corps of officers in the army; there is no such thing as either drinking or gambling going on." However, in 1777 a fresh regiment was raised for the express purpose that the Duke of Hamilton might have the pleasure of commanding it; and though he soon grew tired of his new vocation, and resigned his commission, he sent first for his friend and made him lieutenant and paymaster. Moore went with the "Hamilton Regiment" to Nova Scotia, and had some hard fighting out there, gaining great credit for personal prowess. Peace was proclaimed before the close of 1783 between Great Britain and her then four enemies: France and Spain, Holland and the United States. Though Britain in those days had much less than half her present population, she was wont most cheerfully to engage in war with three or four nations at one and the same time, apparently without any serious misgivings as to results. The "Hamilton Regiment" being disbanded, Captain Moore, then aged only twenty-three, went home to live with his parents in London. He studied hard, and was much in society, being a universal favourite. Through the influence of the Duke of Hamilton, with whom when possible he always spent two autumn months, he was chosen to represent in Parliament four Scottish boroughs, but it was with the express stipulation on his part that he should be in all cases free to follow his own judgment. He never had been, and he never became in the true sense a party-man, but had friends on all sides, friends who held every variety of political opinion. Moore fought for country, not for party. In 1787 he was appointed Major of a new battalion at Chatham, and he gladly forsook civil for military duties. During the following year he rejoined his first regiment, the 51st, at Cork, and soon became Lieutenant-General. While he was there young Anderson, an Ensign in his regiment, became one of his most devotedly-attached friends, and was ever after his inseparable companion. By this time he was known as a disciplinarian of unusual power, indulgent when he might safely be so, but inflexible in enforcing strict obedience. In an age when hard drinking was the fashion, he set his face like a flint against habits of intemperance, alike in the ranks and among officers, from most of whom he had steady support. One young lieutenant, who ventured to appear on parade in a state of intoxication, was forced by him to resign the service, and from that time Moore had no further trouble. His regiment became widely known for its exceptional sobriety and dependableness.