Includes: correspondence between MS, Sarah Oliver [earlier Sarah Churchill, later Sarah Beauchamp and Sarah, Lady Audley] and Clementine Churchill (copies and originals), on subjects including MS going up to Liverpool to see [? HMS Gurkha] and Sarah's training in the Women's Auxiliary Air Force (WAAF) and her future war work, also including a copy of a letter from Sarah to John Paddy Carstairs on his films for the Ministry of Information; copies of letters from MS to her cousin Judy Montagu, on subjects including her visit to Liverpool, War Weapons Week, various parties, her engagement to Lord Duncannon [later 10th Lord Bessborough] and joining the ATS [the Auxiliary Territorial Service]; letters from MS to Clementine from Holyroodhouse, Edinburgh [Scotland], May 1941, when she was serving as a maid of honour to Sir Iain Colquhoun [Lord High Commissioner to the General Assembly of the Church of Scotland], also on the end of her engagement to Lord Duncannon.