George Augustus - Prince of Mecklenburg-Strelitz
Son of Charles Louis Frederick, Prince of Mecklenburg-Strelitz (1707-1752) and Elizabeth Albertine, Princess of Saxe-Hildburghausen (1713-1761). Brother of Queen Charlotte Sophie (1744-1818) of England. Officer in the 4th Regiment of Austrian-Salzburg Dragoons, reaching the rank of Major-General in the Austrian army.
Boswell met the young prince a couple of times in The Hague in January, 1764, where they supped and played billard together.