Biographical accounts and military notebooks: 'Some account of General George Ainslie', covering his career, family and descendants to c.1887; account of Ainslie's brothers, sisters and descendants to c.1895; commission in the Horse Grenadier Guards, signed by George II, 1755; muster roll, Captain George Ainslie's troop in the 15th Light Dragoons, 1759-60; Ainslie's notebook in Poland, Silesia and Romania, 1772; and a document appointing Ainslie Governor of the Scilly Isles (1783).
Correspondence: Letters to Ainslie from Prince William of Brunswick (1762); Charles, Prince of Brunswick and Frederick the Great (copy replies, 1772); Hugh Elliot (1773); Count de Romanzow, Kainardgi, Bulgaria (1774); Sir Thomas Wroughton, British Minister, Warsaw (1775); Sir John Floyd (3 letters, 1776-78); John Jaffray (1781); 10th Earl of Pembroke (1782); G.A. Eliott, 1st Baron Heathfield, Gibraltar (1785); Sir William Fawcett (1787); Frederick Augustus, Duke of Brunswick-Luneburg, Berlin (1789); [H]. Cradock, Dublin (1789); Robert Craufurd (1790); Sir Sidney Smith, Constantinople (1793); Henry Dundas, 1st Viscount Melville, Secretary of State (instructions to join the Prince of Orange in Holland and the command of forces at Ostend) (2 letters, 1793); 1st Baron Auckland, The Hague (1793); Sir William Erskine, East Flanders (copy letter of Sir James Murray, 1793); John Whitelocke, Kingston, Jamaica (1793); Frederick, Duke of York, Furnas and Rousselaar (2 letters, 1793); Gideon Duncan, Commissary, Ostend (1793); Col. Carl von Wurmb, Nieuport (1793), Sir James Murray, Menin and Englefontaine (1793); Sir Adam Williamson, Port au Prince (1795); Sir Charles Colville (1801); and George, Duke of Kent, Gibraltar (1802). There are also letters from Ainslie to Frederick the Great (1772) and Robert Ainslie (uncle) (1774).