How to look for records of... International boundaries in maps, surveys and other records

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1. What are international boundaries?

Since early times, rulers and governments have been concerned to define and protect the limits of their authority and to defend their frontiers against invasion and conquest – Offa’s Dyke and Hadrian’s Wall are well-known examples of early attempts to demarcate frontiers. Later, boundaries were often defined verbally, a practice which left much scope for confusion and dispute. From early modern times, western civilisation has become increasingly dependent on maps to define territory, whether that territory be an individual dwelling, a local jurisdiction or a frontier between sovereign states, but the practice of accurately surveying and mapping international boundaries did not become the norm until the nineteenth century. Many international boundaries remain in dispute today, and the records of earlier definitions, demarcations and surveys are frequently consulted. Such records may be cartographic or textual.

The conduct of official relations between Great Britain and other countries has always been a function of central Government. The simple division of responsibility for the conduct of foreign affairs between the Secretaries of State for the Northern and Southern Departments was superseded in 1782 by the creation of the Foreign Office. The administration of most British colonies overseas was the responsibility first of the Board of Trade and subsequently of the Colonial Office; however, the Indian sub-continent and a number of other territories east of Suez were separately administered by the East India Company and subsequently by the India Office (records not in The National Archives). As a number of colonies became independent, their new status as dominions was recognised by transferring responsibility for the conduct of relations with such former colonies to the Dominions Office, subsequently the Commonwealth Relations Office. Since 1968, relations with all overseas territories, regardless of status, have been the responsibility of the Foreign and Commonwealth Office. For this reason, The National Archives is one of the richest sources in this country of archival material relating to international boundaries.

2. Public records of maps, surveys and other records

The public records contain maps, surveys and other records relating to international boundaries in a surprisingly large number of areas. There are two principal reasons for this:

  • British colonial interests were carefully nurtured and jealously guarded. In Africa, Asia and the Americas, it became increasingly common for the boundaries between British colonies and neighbouring colonies of other European nations to be defined by treaty, demarcated on the ground by an international boundary commission, and delineated on a record map to be preserved among the archives of both the colonial powers concerned.
  • In the 19th and early 20th centuries particularly, British surveying expertise and political impartiality were universally respected, with the result that there was frequently a British commissioner on international boundary commissions even when Britain had no direct interest in the territories affected. The definitive records of such surveys were normally deposited in the archives of the countries most directly interested or in the archives of the responsible colonial powers, but a certified copy was normally brought back to London by the British commissioner and deposited among the archives of (usually) the Foreign Office.

As time has passed, archives in many countries have been destroyed by war, natural disasters or major changes in government. As a result, documents now in The National Archives often constitute the sole surviving record of earlier boundary surveys.

It is important to emphasise that maps constitute only one of a variety of documents which may be of use in establishing the history and course of a boundary, and that they should not be used in isolation. Explanatory memoranda, diplomatic despatches, official reports by boundary commissioners, cahiers de spécification, survey data, treaties, photographs: these are only some of the documents which may explain or supplement maps. Most of the maps in The National Archives were produced in a specific administrative context: an understanding of that context and of all the documents created in conjunction with a given map is essential for a valid interpretation of the map. Maps are no more infallible than any other documents created by human beings, and the use of related documents can help to identify deficiencies in the maps. Particularly useful in this context are likely to be manuscript drafts, printers’ proofs and other preliminary versions of definitive maps, but such documents do not always survive.

3. Records containing documents relating to international boundaries

It may generally be assumed that all series of Foreign Office, Colonial Office and Dominions Office original correspondence and confidential print are likely to contain material relating to international boundaries if the country to which they relate was involved in a boundary dispute. The archives of British embassies and consulates (among the records of the Foreign Office) and of British High Commissions (among the records of the Dominions Office and successors) are equally rich sources, as are confidential print classes, many of which contain printed versions of boundary maps. Records relating to the colonies of foreign countries are among the Foreign Office records relating to the appropriate colonial power.

Both the Foreign Office and the Colonial Office created series of registers and indexes to serve as means of reference to the original correspondence. During the nineteenth century, the Foreign Office began the practice of ignoring the above arrangement and binding together in strict chronological order large accumulations of papers relating to important topics; such accumulations were called ‘cases’. The Foreign Office compiled a separate index to cases, a copy of which is available in the reading rooms at The National Archives: this can be a useful means of reference to primary records about international boundaries. The Foreign Office also bound much of its general correspondence relating to maps in a separate series of Library ‘cases’ (in FO 83): these include, for example, a number of papers about maps of the boundary between the United States and Canada and maps of boundaries in the former Ottoman Empire after 1878. They also contain information about map production, accuracy, printing, distribution etc.

In 1906, the Foreign Office changed its registry system: thereafter, records are arranged by the Foreign Office department which created them, rather than by the country to which they relate. A single index was created, initially on cards and from 1920 in printed form. The printed indexes have been reprinted by Kraus-Thomson and are widely available in academic and other major reference libraries. It should be emphasized that the paper numbers, file numbers and other references given in all these means of reference are those which were in use in the department concerned when the records were created; they need to be keyed up to Discovery, our catalogue, or to the modern series lists in The National Archives in order to identify the reference by which a document may be requisitioned by readers. It should also be remembered that the indexes contain references to many documents which do not survive.

Papers of many individuals – civil servants, politicians, Army officers etc – are also in the National Archives. Depending on the official activities of the person concerned, such papers are likely to contain information about – and maps depicting – boundaries: the papers of Major General Sir John Ardagh (PRO 30/40) and of Field Marshal Sir J.L.A. Simmons (FO 358), for example, contain material about the Turco-Greek frontier, while those of Lord Cromer (FO 633) and of Sir Edward Grey (in FO 800) contain material about the Aqaba boundary.

The minutes and memoranda of the Cabinet and its numerous committees, and records relating to high-profile conferences (also among the records of the Cabinet Office) contain many maps of international boundaries. Such maps were usually printed at a small scale to illustrate discussion papers or to provide background information.

4. Selective list of record series known to contain maps of international boundaries

The following is a necessarily selective list of record series which are known to contain maps of international boundaries. It should be noted that the dates given are the dates of records which have been transferred, not necessarily the dates of records which are available for public inspection.

Record series Specific records and dates
CAB 61 Cabinet Office: Irish Boundary Commission. 1924 to 1925. Minutes, papers, correspondence and report of the Commission; oral and written evidence submitted; and numerical census (heads of households named) of Castlederg, Clogher and Dungannon Unions, and Omagh Urban District.
CO 6 Colonial Office: Original Correspondence: British North America. Includes papers, 1816 to 1868, relating to the boundary between British North America [Canada] and the United States of America pursuant to the Treaty of Ghent (see also FO 303); and report of Commissioners appointed under the Treaty of Washington (1848 to 1850).
CO 700 Colonial Office: Maps and Plans: Series I. 1595 to 1927. The earlier part of the principal collection of maps accumulated by the Colonial Office. Includes numerous maps of boundaries of British colonial territories. See also CO 1047 and CO 1054.
CO 1047 Colonial Office: Maps and Plans: Series II. 1779 to 1947, but predominantly 1910 to 1940. See also CO 700 and CO 1054.
CO 1054 Colonial Office and successors: Maps and Plans: post-1940 Collection. 1897 to 1984, but predominantly after 1940. See also CO 700 and CO 1047.
FO 93 Foreign Office: Protocols of Treaties. 1695 to 2003. Many treaties contain maps showing a boundary as envisaged during negotiations but before demarcation on the ground. There is a typescript Index to Important Treaties 1635-1913 in the reading rooms at The National Archives.
FO 96 Foreign Office: Miscellanea: Series II. Includes financial accounts relating to the North American Boundary Commission 1843-1848; papers of the Serbian Boundary Commission 1878-1880; and printed material from the India Office relating to the North-West Frontier.
FO 302 Foreign Office: Archives of Commissions: America: North-West Boundary. 1872 to 1876. Correspondence, letter books, register, accounts, maps. Includes an album of photographs of the Commission at work.
FO 303 Foreign Office: Archives of Commissions: America: Treaty of Ghent. 1796 to 1829. Journals, British and American memorials, reports etc. See also CO 6.
FO 304 Foreign Office: Archives of Commissions: American Claims, 1794. Includes a minute book of the commissioners appointed under Article 5 of the Treaty of Amity, Commerce and Navigation between Great Britain and the United States to decide on the identity of the River St Croix named therein as a boundary line.
FO 367 Foreign Office: African Department: General Correspondence from 1906. 1906 to 1913. After 1913, included in FO 371.
FO 371 Foreign Office: Political Departments: General Correspondence from 1906. 1906 to 1966.
FO 372 Foreign Office: Treaty Department and successors: General Correspondence from 1906. 1906 to 1967.
FO 373 Peace Conference of 1919 to 1920: Handbooks. Prepared by the Historical Section of the Foreign Office for the use of officials attending the conference, and subsequently issued to the public in modified form. Many contain maps illustrating the history of international boundaries under consideration at the end of the First World War.
FO 608 Peace Conference of 1918 to 1920: Correspondence. Includes numerous files about the boundary changes following the end of the First World War.
FO 867 Foreign Office: Anglo-Egyptian Sudan. Includes minutes and correspondence, 1931 to 1954, relating to the Darfur-Wadi boundary.
FO 925 Foreign Office: Maps and Plans. 1700 to 1944. The principal collection of maps accumulated by the Foreign Office. Includes numerous maps of international boundaries in the demarcation of which Britain played a role.
FO 928 Archives of Commissions: Argentine-Chile Boundary Arbitration, 1966 to 1967.
FO 1049 Control Commission for Germany (British Element): Political Division. 1943 to 1951. Includes maps of boundaries between the British Occupation Zone and neighbouring countries, and of inter-zonal boundaries.
HO 267 Imperial Governor to the Secretary of Northern Ireland: Correspondence and Papers. Includes files on the Irish Boundary Commission.
OD 6 Directorate of Overseas Surveys: Registered Files. 1939 to 1990. Contains a small number of files about the Kenya-Ethiopia boundary.
SP 103 State Papers Foreign: Treaty Papers. 1577 to 1780. Formal documents and papers connected with negotiations conducted by English ministers and plenipotentiaries.
SP 108 State Papers Foreign: Treaties. 1579 to 1780. There is a typescript Index to Important Treaties 1635-1913 in the reading rooms at The National Archives.
WO 33 War Office: O and A Papers. 1853 to 1969. Printed reports, memoranda etc, comparable to Foreign Office and Colonial Office Confidential Print.
WO 106 War Office: Directorate of Military Operations and Intelligence. 1837 to 1961.
WO 181 War Office: Directorate of Military Survey: Papers. 1887 to 1985. Unregistered files of the Geographical Section, General Staff. Many relate to boundary surveys: the Middle East and north Africa, as well as former British colonies.

5. Maps outside The National Archives

A number of other institutions have significant holdings of maps relevant to studies of international boundaries. Particularly of note are:

6. Other bodies

International Boundaries Research Unit, Department of Geography, Durham University.

7. Further reading

Some or all of the recommended publications below may be available to buy from The National Archives’ Bookshop. Alternatively, search The National Archives’ Library to see what is available to consult at Kew.

John B Allcock (ed), Border and territorial disputes (3rd edition, Harlow, 1992)

Louise Atherton, ‘Never Complain, Never Explain’: Records of the Foreign Office and State Paper Office 1500-c1960 (PRO Readers’ Guide No 7, PRO 1994)

Mandy Banton, Administering the Empire, 1801-1968: a guide to the records of the Colonial Office in The National Archives of the UK (Institute of Historical Research and The National Archives, 2008)

Ian Brownlie, African boundaries: a legal and diplomatic encyclopaedia (London, 1979)

Edward Hertslet, The map of Europe by treaty, 1814 to 1891 (4 volumes, London, 1875-1891)

Edward Hertslet, The map of Africa by treaty (3 volumes, London: 2nd edition 1896, 3rd edition 1909)

Michael Roper, The records of the Foreign Office 1782-1968, Public Record Office Handbooks No33 (Public Record Office, 2002)

British and Foreign State Papers: compiled by the Foreign Office librarian, these volumes cover the period 1812 to 1968 and contain the printed texts of treaties, conventions, major diplomatic correspondence and other important papers. They are not confined to British interests, and include the texts of many treaties, boundary agreements and similar documents relating to areas in which Britain had no direct interest.

List of Colonial Office Confidential Print to 1916 (PRO Handbook no 8, HMSO 1965)

Guide reference: Overseas Records Information 37