He was promoted to commander of in
Jamaica on 1 May 1744. On 9 November 1745 he was attacked and captured by two Spanish
privateers off the
Black River, after stiff resistance. Shuldham suffered mistreatment by privateers, but was compensated by the Spanish governor of
Havana. After finally returning to England, he was promoted to be captain of on 12 May 1746, then employed on the coast of Scotland; in December 1748 he was appointed to , and in March 1749 to . In October 1754 he was appointed to , from which, in March 1755, he was moved to the 60-gun , going out to the
West Indies, where, near
Martinique on 11 March 1756, she fell in with a French 74-gun ship and two frigates, which overpowered and captured her.
Seven Years' War War had not then been declared, but hostilities had been going on for several months, as Shuldham very well knew, and the story that he mistook the enemy's ships of war for merchantmen would be but little to his credit if there was any reason to suppose it true. He, with the crew of the
Warwick, was sent to France, kept a prisoner at large at
Poitiers for nearly two years, and returned to England in a
cartel on 16 March 1758. A court-martial acquitted him of all blame for the loss of the ship, and on 25 July 1758 he was appointed to , in which he joined Commodore
Sir John Moore in the West Indies and took part in the
reduction of Guadeloupe and its dependent islands, March to May 1759 under Commodore Moore. In July he was moved by Moore into , which was lost on a reef of rocks at
Fort Royal off
Martinique as she was standing in to engage a battery on 8 January 1762, when the island was attacked and reduced by Rear-Admiral
Rodney. In April Rodney appointed Shuldham to
HMS Marlborough, from which a few days later he was moved by Sir
George Pocock to , and again by Rodney after a few weeks to
Foudroyant. In mid-1763 he was transferred once more to a temporary command aboard , with which he returned to England in August 1763. Peace had been declared between England and France, and Shuldham was ashore on
half-pay until December 1766, when he was appointed to , the
guardship at
Plymouth. In November 1770 he transferred to , then commissioned in consequence of the expected rupture with Spain.
Governor of Newfoundland On 14 February 1772 he was appointed commodore and commander-in-chief on the
Newfoundland Station, which office he held for three years. He was responsible for the construction of
Fort Townshend, which was completed in 1780. Shuldham visited
Chateau Bay on the
Labrador coast and sent his lieutenant,
Roger Curtis, to inspect the northern coast and the
Moravian missionaries. ==Flag rank==