Born the son of Richard Troubridge, a baker, Troubridge was educated at St Paul's School, London. He entered the Royal Navy on 8 October 1773 and, together with Horatio Nelson, served in the East Indies in the frigate "Seahorse". Promoted to lieutenant on 1 January 1781, he took part in the Battle of Sadras in February 1782 during the American Revolutionary War and the Battle of Trincomalee in September 1782 during the Anglo-French War. His first command was the sloop "Lizard" in October 1782.