 In 1757 as Lieutenant he accompanied Sir John Mordaunt's expedition to Rochefort, France.From 1760 during the Seven Years' War he served as aide-de-camp to General Henry Seymour Conway, and appears to have liaised with Prince Ferdinand.He ended up at the siege of Kassel in 1762, returning with the regiment in 1763, thereafter assisting it to build roads in Scotland until 1764.