The earliest papers are dated 1779, when Macartney was Governor of the Cariboo Islands, and describe the British surrender to the French during the American War of Independence. Thereafter, the papers relate to the first British Occupation of the Cape of Good Hope and, in particular, to the years 1797-1798 when Macartney was Governor. There are also papers relating to the administration of Sir James Henry Craig, who captured the Cape on 14 September 1795, and was in command until Macartney arrived in 1797.

All aspects of administration at the Cape are touched upon: - shortages of grain, specie (NB: money in the form of coins rather than notes) and timber; the duties of the Burgher Senators (the new name for the old Commissioners of the Court of Justice under the Dutch East India Company); slavery and the importation of slaves; the disaffection of the Dutch population; the indigenous tribes and the need to 'separate' them from the colonists; trade regulations for the Cape and the East India Company's monopoly of trade to and from the East; fiscal arrangements; the question of the debts due to the Dutch East India Company at the time of the capture in 1795 and whether they are to be regarded as prize booty for the captors of the Cape or are to be taken over by His Majesty's government in London. Of particular interest are the reports sent back by Macartney's private secretary, John Barrow, who had been sent on an expedition to investigate supplies of timber, flax and hemp, the existence of mineral deposits, the navigability of certain bays and trading with the "Caffres".

The papers also relate to the Napoleonic Wars and to the Cape's strategic position. There is much about the war at sea, which necessitated the introduction of a convoy system for shipping, and about the military and naval forces at the Cape, including plans for projected attacks on Batavia and Spanish America from the Cape. Many items relate to the naval mutiny at Simon's Town in 1797.

Amongst the British correspondents is the Court of Directors of the East India Company, the Privy Council., Henry Dundas, Secretary of State for War, and William Huskisson, Under-Secretary for War. At the Cape Macartney corresponded with Admirals Pringle and Christian, Major-General Duncan, Commander of the troops, Secretary Andrew Barnard, Under-Secretaries John Barrow and Acheson Maxwell, Deputy Secretary Hercules Ross, Commissary-General John Pringle, the landdrost at Graaff Reinet, Frans Reinhard Dresler, and others.

There in one additional intrusive item (No.594) about the Cape Observatory, dated 1837 and written by Sir John Barrow, who had been closely associated with Macartney at the Cape.