The collection contains letters, manuscripts and documents sent mostly to Henry Dundas, 1st Viscount Melville (Home Secretary, Secretary of State for War, First Lord of the Admiralty) and some to his son Robert Saunders Dundas, 2nd Viscount Melville (President of the Board of Control for India, First Lord of the Admiralty). The collection principally focuses on British possessions in India, the East Indies and the West Indies; relations with the United States; and hostilities, negotiations, and political maneuvers with other European powers, especially with France and Russia.