The John Simcoe papers are a miscellaneous collection of letters and documents pertaining to Colonel Simcoe's military career in the British Army during the American Revolution and his post-war life. The collection contains letters between Col. Simcoe and a variety of correspondents. Most prominent are 23 letters from General Sir Henry Clinton, dated 1782-1792; letters and documents related to the Queen's Rangers, including military orders and returns, dated 1774-1799; nine letters from Col. Henry Caldwell regarding a monument to General James Wolfe, dated 1802-1804; and letters between Simcoe and George Hammond, the first British minister to the United States. Several unofficial documents relate to Simcoe's advancement and the disposal of his Canadian estates. Other miscellaneous letters and documents include one by Margaret Graves, in which she defends the conduct of her husband, Admiral Samuel Graves, in Boston before the outbreak of the Revolutionary War.
The collection contains one "Memorandum Book," which is made up of copies of letters and military orders written for Simcoe by his Secretary, Major Edward Baker Littlehales, dated 1792-1793. Maps from the Simcoe papers have been transferred to the Map Division, including several attributed to John's wife, Elizabeth Simcoe. An unsigned commonplace book and a selection of literary drafts (including one for Simcoe's publishedRemarks on the travels of the Marquis de Chastellux in North America, 1787) and fragments of other works complete the Simcoe papers