These consist of original despatches, letters and papers sent to the Secretary-at-War, 1755 to 1795, and to the Secretary of State for War, 1794 to 1865. Those sent to the Secretary of State relate for the most part to the conduct of the French Wars or to the military business of the Colonial Office (CO) from the late 1840s onwards. There are also some bundles of correspondence sent to the Commander-in-Chief (or to his subordinates the Military Secretary and the Adjutant-General); and some miscellaneous books. The series also contains letters, catalogued in detail, from Philip D' Auvergne, Prince de Bouillon.