Maurice's grandmother was Sir Robert Walpole's sister. It is assumed that Walpole was influential in getting Maurice started on his Naval career. Maurice also had an ancestral tie to a Captain Galfridus Walpole who had served in the Royal Navy with distinction and who lost his right arm in a naval battle against the French in Vado Bay in March 1711.
During the Seven Years War with France, Maurice was the commander of a ship called Dreadnought which was in action in the Battle of Cap-Francais off Saint-Domingue in the Caribbean in 1757.
Once established in the Navy, Maurice was able to help his sister's son to also join. His sister was Catherine Nelson nee Suckling and her son was to become the famous Admiral Lord Horatio Nelson. Horatio joined the Raisonnable in 1771, commanded by his uncle. Another nephew, Lieutenant Maurice William Suckling (1761-1820), was also helped into the Navy by Maurice.
In 1775 Maurice took up a job at the Naval Office as Comptroller of the Navy taking over from Sir Hugh Palliser. Maurice is mentioned in the diary of George Marsh, Commissioner of the Navy, (page 139, Feb 1776) with reference to a meeting with the Prime Minister Lord North where they were discussing how to obtain more shipping to transport troops to fight in America.
Maurice died in 1778 and his position as Comptroller of the Navy was taken over by Rear Admiral Sir Charles Middleton .
(George Marsh) (Diary of George Marsh)