Hardinge's papers are divided into two series: manuscripts and correspondence. The manuscripts comprise about 550 documents, reports, memoranda, etc. relating to Hardinge's work as a career soldier and administrator. The Indian phase of his career is the least well covered. Many of these documents were written by others, such as the Duke of Wellington or Lord John Russell, though they contain Hardinge's marginal notes. Papers on the British Army cover such topics as religious services for soldiers, 1823-1844; the organization and reform of military supply departments, 1822-1830; an inquiry into British military education, 1822-1829; and the organization of the Medical Department, 1812-1828. Material on the Home Army covers the period 1814-1850 while material on Ireland, 1816-1843, concern not only the militia, but also more wide ranging economic, social and political issues, such as the commutation of tithes. Papers on British North America, 1815-1844, concentrate on defence of the St. Lawrence Valley and the Maritimes, with special emphasis on canals (Rideau, Lachine, Welland). The strength, distribution, health problems and pay of troops in India, 1846-1847; the fortification of Aden, 1825-1847; and military matters pertaining to the West Indies, Bermuda, Australasia, South Africa, Mauritius, China, the Iberian peninsula and the Crimea are also discussed. It should be noted that the Australian papers also contain a considerable body of civilian population statistics. Hardinge's files also contain materials on military finance, particularly army estimates, 1826-1844; half-pay and pensions, 1812-1832; pay and allowances, 1827-1841; and the finances of the War Office, 1803-1847. Finally, a section of miscellaneous papers includes addresses by Hardinge, memorials of civil and military officers, cases of military discipline, proposals for new weaponry, and some documents on the reorganization of the government in 1827. The only items of personal interest concern the duel between Wellington and Lord Winchelsea, in which Hardinge was Wellington's second. The Hardinge correspondence is of much the same character as the manuscripts. It comprises over 2,000 letters, the largest blocks falling in the periods 1828-1831, 1842-1844, and 1852. There is a particularly substantial body of letters from Wellington and Lord Londonderry. Supplementing these papers is a microfilm of Hardinge materials in Cambridge University Library. These place more stress on the Indian period, with a large number of letters from Sir Robert Peel.

Container 1 holds Hardinge's correspondence dated between 1822 and 1829.

Container 2 holds Hardinge's correspondence dated between 1829 and 1831.