The largest section of the Buchanan Collection consists of the correspondence of Sir Andrew Buchanan, 1st Baronet. Much of the correspondence is official and highlights British diplomatic interests in the majority of the countries in which Sir Andrew Buchanan served (although no records survive from his earliest postings). The papers also reflect general foreign policy interests during this period, and contain comments on news about political developments in Britain. The letters contain advice from officials in the foreign office and instructions regarding foreign policy. Correspondents include many leading British political figures, such as the Earl of Aberdeen, Viscount Palmerston, Lord John Russell and the Earl of Derby. (Bu)
The second section of the collection consists of diaries and correspondence of Sir George Buchanan during his diplomatic service in Russia and the letters, diaries, press cuttings and photograph albums of his daughter, Meriel, who accompanied him. (Bu B)
The papers of Eric Buchanan, third baronet, include a quantity of correspondence relating to the Tennant family from whom his wife, Constance Tennant, was descended. There is also material relating to his receipt of the Queen's medal at Wellington College and correspondence from Sir Eric to his wife. (Bu C)
Charles Buchanan's papers consist chiefly of correspondence with family members and material relating to his military service in India, 1928-1932. (Bu D)
The final section contains papers of Sir Andrew Buchanan, fifth baronet. This small collection contains a series of papers and correspondence relating to V.A.C. Harbord who was a page at the coronation of George V, alongside miscellaneous items on members of the Buchanan family and correspondence relating to the death of Mary Constance Victoria Mayhew. (Bu E)