Gosselin joined the Royal Navy on 2 August 1778 as a follower of Captain Philip Boteler in the brand new frigate . He later transferred with Captain Boteler to the ship-of-the-line in June 1779. On 16 August "Ardent" was captured by a combined Franco-Spanish fleet near Portsmouth. Gosselin spent three months as a prisoner of war at Alençon. After his release he joined the ship-of-the-line , the flag ship of Rear-Admiral Sir Samuel Hood, on 11 October 1780. On "Barfleur" Gosselin took part in a number of major actions of the American Revolution as a part of the fleet of Admiral Sir George Rodney, including the Battle of Fort Royal, Battle of the Chesapeake, and the Battle of Saint Kitts. After this battle Gosselin transferred to the frigate commanded by Rear-Admiral Hood's brother, Captain Alexander Hood. In "Champion" Gosselin then participated in the Battle of Delaware Bay and the Battle of the Saintes, where the French admiral François Joseph Paul de Grasse surrendered. Gosselin was also present at the Battle of the Mona Passage where a squadron under Rear-Admiral Hood captured an escaping French squadron, with "Champion" capturing a French corvette. In June 1782 Gosselin transferred with Captain Hood to the frigate HMS "Aimable", serving in her until the American Revolution ended with the Treaty of Paris in 1783. He returned home on 26 June 1783.