Internationalism in Cartography

Below, project director Matthew Edney takes an in-depth look at the topic of international collaboration that we highlighted in our 2023 outreach letter.

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One of the primary themes running through Cartography in the Nineteenth Century, Volume Five of The History of Cartography, is the development of international cooperation in mapping. International teams collaborated on boundary surveys, but only because they had to [fig. 1]. More calculated cooperation was initially rather disorganized and incoherent: different groups of mapmakers and map scholars worked across national divides for various reasons. Nonetheless, cooperative efforts laid the foundations for further and more organized collaborations in the twentieth century that, among other things, shaped the study of map history and gave rise to The History of Cartography.

Figure 1. Detail of sheet XIII of the “Carte spéciale de la nouvelle frontière entre l’empire de Russie et la Royoume de Suède” (1810). This figure will appear in Volume Five, in Michael Jones and Venke Asheim Olsen’s entry on “Boundary Mapping in the Nordic Countries.” Riksarkivet, Stockholm (SE/A/81007/4/4.1/0003:00004).

International Geodetic Cooperation

There had, of course, been some international elements to mapping endeavors before 1800, as described in Volume Four of The History of Cartography. Notably, there was a constant interchange among the engineers in the armies of Western Europe. For example, a French-born engineer, Simon Lefebvre, was recruited while serving in the Netherlands to work for Frederick II of Prussia, for whom Lefebvre wrote the Essai sur la maniere de faire les cartes (1762) [fig. 2]. An Austrian officer and surveyor, Anthony Troyer, ended up in southern India when his British patron, Lord William Cavendish Bentinck, became governor of Madras (modern Chennai); there Troyer set up a school to train infantry officers in land surveying, thus introducing the plane table to British India. The “remarkable” result of the networking and exchange of individual surveyors, as Brian Harley (1978, 45) wrote in one of his chapters on the mapping of the American Revolutionary War, was the “common approach to the making and use of maps” taken by the European militaries. The other main arena of international cooperation in the Enlightenment was in geodetic work to measure the size and shape of the earth. Spanish and Swedish scientists accompanied the French expeditions to Peru and Lapland to measure the earth’s size and shape in 1735–45, and British and French astronomers and geodesists collaborated in 1784–90 to measure the precise longitudinal distance between the observatories of Greenwich and Paris [fig. 3].

Figure 2. Simon Lefebvre, Cours du Fleuve st Laurent depuis Montreal jusqu’a Tadoussac 1762, in his Essai sur la maniere de faire les cartes (Berlin, 1762), pl. 2 (Kershaw 1993–98, 2:274–75, item 659). Extending the idea of internationalism, Lefebvre used the recent British conquest of New France as the basis for a thought experiment to explain how a state like Prussia could undertake a triangulation-based survey of its territory. Lefebvre’s work prefigured the British mapping of the St. Lawrence Valley, led by the Dutch-born Samuel Holland (Hornsby 2011). Holland’s map work was not, however, based on triangulation, and Lefebvre’s triangulation is purely fictional. Copper engraving, 22 × 35 cm. Courtesy of the Sächsische Landesbibliothek—Staats- und Universitätsbibliothek, Dresden (Geodaes. 125). To view in high resolution and learn more, click on image or visit
Figure 3. Plan of the Triangles Whereby the Distance between the Royal Observatories of Greenwich and Paris Has Been Determined, in William Roy, “An Account of the Trigonometrical Operation, whereby the Distance between the Meridians of the Royal Observatories of Greenwich and Paris Has Been Determined,” Philosophical Transactions of the Royal Society of London 80 (1790): 111–270, pl. 9. Copper engraving, 31.5 × 64.5 cm. Courtesy of the Department of Special Collections, Memorial Library, University of Wisconsin–Madison; online at Click on image to view in high resolution (scroll to page 172).

A primary goal of nineteenth-century geodesy was to link together the triangulation networks created by each state territorial survey in order to make geophysical studies more consistent. Put simply, geodesists, astronomers, and physicists came to realize that the earth is not actually a nice, neat spheroid but is actually an irregularly shaped body. (The modern term is that the earth is a “geoid,” which means an earth-like shape.) And until the actual shape, defined by its gravitational field, was determined, all sorts of problems could not be solved. Indeed, the British astronomer George Biddell Airy (1845, 165) held up geodetic studies of gravity as “affording the most satisfactory proof that we can expect ever to have” of Sir Isaac Newton’s “Principle of Gravitation.”

The completion of major geodetic surveys served to prompt further work to connect them all. Having published the final observations for his massive meridional arc through Russia from Finland to the Black Sea (1816–55), Wilhelm Struve traveled around Europe to promote the unification of all the triangulations across northern Europe. Struve’s proposal induced Airy to have the Ordnance Survey resurvey the longitudinal series from the west coast of Ireland to the Greenwich observatory and, with French cooperation, to extend that series to connect to the French and Belgian triangulations [fig. 4] (James 1863, iv). Struve’s cause was taken up by the retired Prussian engineer General Johann Jacob Baeyer, whose long memorandum convinced the Prussian authorities to support a mitteleuropäische Gradmessung (Baeyer 1861). Six other German states and nine other countries rapidly signed onto the plan, and the first international conference of the Central European Arc Measurement was convened in Berlin in 1864. The organization possessed a Central Bureau that managed operations, overseen by the Permanent Commission, which met annually, and the General Conference, which met every three years. In 1867, it was enlarged as the European Arc Measurement [fig. 5], which in turn was a founding partner in the formation in 1919 of the International Association for Geodesy (Torge 2007, 213–40; Torge 2015).

Figure 4. Untitled plans of the longitudinal triangulation from the west coast of Ireland to the Greenwich observatory (upper) and from Greenwich across into western Belgium (lower), in Henry James, Extension of the Triangulation of the Ordnance Survey into France and Belgium (1863), pl. 1. Lithograph, 31 × 24 cm (paper). Courtesy of Cartographic Associates (6894.007). To view in high resolution and learn more, click on image or visit
Figure 5. Anibale Ferrero, Red Geodésica europea para la determinación de la figura y dimensiones de la tierra (Madrid: Instituto Geográfico y Estadistico, 1881). One of many such maps of European triangulation networks published in association with the International Association for Geodesy and its predecessor institutions. Lithograph, 61 × 74 cm. Courtesy of the Biblioteca Nacional de España. To view in high resolution and learn more, click on image or visit

The International Map of the World

The spread after 1790 of systematic territorial mapping programs grounded in triangulation gave rise to the widespread expectation that all regional and even world mapping should be based on those surveys. Even if they were not currently grounded in territorial surveys, practitioners and even some members of the public anticipated that regional maps would eventually be so. The British geographer Julian Jackson—who had a suitably international career, first as an artillery officer in India (1808–13) and then as a staff officer for the imperial Russian general staff (1815–30) before retiring to London (Goudie 1978)—stated the expectation clearly in a mid-century textbook on cartography:

Thus, the interior of South America, though, to the eye, well filled in upon the [regional] map, offers but a distant approximation to truth; and when, in after years, the axe shall have cleared the secular forests of that portion of the New World, and the vast regions that extend from the Andes to the Atlantic, shall be covered with the abundant harvests and the habitations of a dense population, the [territorial survey] maps of the country then constructed will, upon a comparison with those now existing, show our descendants how wide of the truth were our [regional] maps in the position of many places, and how totally different the true course of its rivers from what we now figure them with such show of accuracy. (Jackson 1852, 164)

The spread of detailed topographical mapping was a marker of the advance of Western civilization. The British geographer John G. Bartholomew demonstrated the connection in a map included within the essay with which he introduced his XXth Century Citizen’s Atlas of 1908 [fig. 6]. Bartholomew used black for areas covered by triangulation-based systematic territorial surveys, red for topographical maps based on “surveys less exact in detail,” dark pink for reliable regional maps based on itineraries and numerous observations for latitude and longitude, and light pink for “general geographical maps” that “in many cases” are “only approximate or hypothetical.” Any areas left white were therefore “unexplored” by Westerners and any maps of them are “merely hypothetical.”

Figure 6. John G. Bartholomew, The Exploration and Mapping of the World, in his “A Century of Geography,” in The XXth Century Citizen’s Atlas of the World (London: George Newnes, 1908), vii–xii, map on xi. Much of the data for this map came from a multipart history of world mapping (Bartholomew 1891). Courtesy of the Geography and Map Division, Library of Congress (G1019 .B43 1908); photograph by Matthew Edney.

Bartholomew presented the territorial mapping of the world as an endeavor that was being pursued as an international and imperialistic effort by European states and their overseas colonies. A few years earlier, the German geographer Albrecht Penck (1892) had suggested that the global mapping effort be properly coordinated and organized by means of a standardized map series at 1:1,000,000 [fig. 7]. After twenty years of debate, in 1909–13, the official mapping agencies in Europe and the United States of America settled on a single set of standards and graphic conventions for the International Map of the World (IMW). World War I brought international cooperation to a crashing halt. Some participating mapping agencies, notably the U.S. Geological Survey pulled back from the project, although after the war the American Geographical Society made its Map of Hispanic America in 107 sheets in line with the IMW standards. World War II again interrupted work on the IMW, although the combatant states produced separate series covering Europe, North Africa, and western Asia at 1:1,000,000 for military planning purposes. After the war, the IMW became a “zombie project,” staggering on because of bureaucratic inertia—something that mapping agencies did because they had already been working on it for decades but with relatively little appreciation or commitment. After 1970, the different agencies involved slowly ceased publishing sheets as they retooled for digital map production, and the IMW was effectively, finally, terminated in 1989 (Pearson 2015; Rankin 2017).

Figure 7. U.S. Army Map Service, La Habana (Havana), International Map of the World at 1:1,000,000, Series 1301, Sheet NF 17, 2nd ed. This map was compiled by the U.S. Army Map Service in 1961 from various sources. Courtesy of the Perry-Castañeda Library Map Collection, University of Texas at Austin. To view in high resolution and learn more, click on image or visit

On the other hand, the International Association for Geodesy and the IMW paved the way for a number of international collaborations in mapping. The extent is readily apparent in Cartography in the Twentieth Century, Volume Six of The History of Cartography, which includes a number of entries starting “International…,” from “International Cartographic Association” to “International Map of the World.” In this global age, any attempt at comprehensive mapping of the earth, its oceans, and its resources has to be based on international cooperation.

International Scientific and Cartographic Cooperation

The nineteenth-century international collaborations on geodetic and topographical surveys were paralleled by the rise of the environmental sciences and their further international collaboration. Geographers, geologists, botanists, zoologists, climatologists, physicists, and ethnographers all emulated the kind of field work that Alexander von Humboldt had popularized at the very start of the century. A variety of scientists funded by states and empires, by corporations and foundations, and by private means spread out to observe and measure the world and its inhabitants; they presented their results in a series of analytical maps in which they sought to espy the spatial laws of nature.

Humboldt worked with Heinrich Berghaus in Gotha in the creation of Berghaus’s grand Physikalischer Atlas (1845–48) that presented a composite of knowledge assembled by the international scientific community about meteorology and climatology [fig. 8], hydrology and hydrography, geology, terrestrial magnetism, botanical geography, zoological geography, anthropology, and ethnography (Camerini 1993). Seeking an international distribution of this work, Berghaus agreed in 1845 to have A. K. Johnston in Edinburgh publish an English-language edition [fig. 9]. Berghaus’s former student, August Petermann, went to Scotland to assist Johnston in the reproduction of the new maps, although he soon moved to London to work as an independent geographer in a Humboldtian vein [fig. 10] (Demhardt 2022). Although Petermann’s work was not necessarily appreciated (Withers 2019), his efforts established firm connections between German and British map publishers that continued through the century, dissolving only with the outbreak of war in 1914 (Scully 2010).

Figure 8. Alexander von Humboldt’s System der Isotherm-Kurven, in Mercator’s Projection, in Heinrich Berghaus, Physikalischer Atlas, 2 vols. (Gotha: Justus Perthes, 1845–48), vol. 1, pl. 1. Color lithograph, 32 × 39 cm. Courtesy of Cartographic Associates (2515.001). To view in high resolution and learn more, click on image or visit
Figure 9. A. K. Johnston, “Illustration of the Glacier Systems of the Alps (Mt. Blanc),” in The Physical Atlas of Natural Phenomena (Edinburgh: A. K. Johnston, 1850), pl. 4, opp. 14. Courtesy of the Osher Map Library and Smith Center for Cartographic Education, University of Southern Maine (OML Collections). To view in high resolution and learn more, click on image or visit
Figure 10. August Petermann, Rough Sketch of Africa, Indicating the Progress of Recent Discoveries and Map of Damara Land and the Adjacent Countries as Explored and Surveyed by Francis Galton Esq., used in Francis Galton, The Narrative of an Explorer in Tropical South Africa (London, John Murray, 1853). This map is an impression that Petermann set aside from the regular printing process and sent to Humboldt in Berlin as a loose sheet. Courtesy of the Staatsbibliothek zu Berlin (Nachlass Alexander von Humboldt, gr. Kasten 4, Nr. 11). To view in high resolution and learn more, click on image or visit

International Geographical Congresses and the History of Cartography

Over the course of the nineteenth century, different groups of scholars came together in international meetings to share data and ideas. The first International Geographical Congress (IGC) was convened in Antwerp in 1871, in large part to promote peace and cooperation after the Franco-Prussian War (1870–71) (Shimazu 2015). Later congresses became a site for all sorts of collaboration and proposals, including Albrecht Penck’s proposition for the International Map of the World during the fourth IGC, held in Bern in 1891.

From the start, the IGCs—and, after 1922, the International Geographical Union (Abler 2015)—promoted the study of the history of cartography. The exhibitions associated with each IGC prominently featured examples of the maps being made by national and commercial mapping agencies [fig. 11], but they soon also included displays of early maps. The Paris IGC in 1875 included an exhibition of early maps from the collections of the Archives nationales and the Bibliothèque nationale de France; the latter’s exhibits constituted “a complete history of cartography, comprising maps dating from the 7th century to the present time” (Anon. 1875, 403–4). The 1896 IGC in London, hosted by the Royal Geographical Society, had a large exhibition installed at the British Museum that included, in temporary housing, an “historical exhibition” organized by E. G. Ravenstein (Mill 1896, app. B, 125–51). Unfortunately, the published proceedings of the IGCs contain no photographs of these historical installations; I would be pleased to know of any that might survive!

Figure 11. An example of the kinds of official military maps displayed at the International Geographical Congresses. This is a detail of a map of Saxony made by the Prussians and displayed at the third IGC in Venice in 1881. This figure will appear in Volume Five, in Peter Collier’s entry on “Military Mapping by the German States.” From George M. Wheeler, Report upon the Third International Geographical Congress and Exhibition at Venice Italy, 1881, Accompanied by Data Concerning the Principal Government Land and Marine Surveys of the World (Washington, DC: G.P.O., 1885), pl. IX.

In addition to presenting papers on map historical topics, participants in the IGCs established a number of commissions to promote the study of early maps by creating facsimile reproductions of key maps. They were not necessarily successful for three reasons: first, wars and other political tensions interrupted and undermined the internationalism of the congresses; second, the commissions were founded on the expectation that national governments would fund the production of the facsimiles, which did not happen; and, third, the commissioners could not agree on just which early maps needed to be reproduced. Charles Perron of Switzerland successfully proposed the formation of a Commission for the Reproduction of Early Maps at the 1908 Geneva IGC; its terms were reformulated in Rome in 1913 before being stopped by the outbreak of World War I. Roberto Almangià of Italy then had the 1928 Cambridge IGC establish a new Commission on Early Maps, with the goal of creating photographic facsimiles in the manner of his own Monumenta Italiae cartographica (1929); however, this commission staggered on through the 1930s without actually creating the putative Monumenta Europae cartographica (Bagrow 1935; Bagrow 1939).

It was only after World War II that Almagià’s commission had any success. The 1949 Lisbon IGC reconfigured it, at his suggestion, as the Commission for the Bibliography of Early Maps, on the principle that a thorough, international bibliography of early maps was needed to establish the priority of eventual facsimile reproductions (Skelton and Codazzi 1949; Almagià 1952). For the 1952 congress in Washington, Almagià prepared an outline report of progress [fig. 12] with example entries for a catalog of mappaemundi (Destombes 1952b) and a preliminary checklist of early printed maps (Destombes 1952a). However, even as the commission published Marcel Destombes’ bibliography of mappaemundi (Destombes 1964), the 1964 London IGC voted to downgrade the commission to a working group. The reasons for the decision remain unclear. I tend to agree with Brian Harley (1987, 19) that the downgrading resulted from geography’s “quantitative revolution,” which made the standard practices of map historians seem outmoded and unscientific.

Figure 12. Covers of the two parts of Roberto Almagià, ed., Rapport de la commission pour la bibliographie des cartes anciennes ([Paris]: Union géographique international, 1952). Photograph by Matthew Edney; author’s collection.

As it happened, the London congress was the occasion for a special, two-day symposium—one of fourteen associated with the congress—dedicated to the history of cartography. It was organized at the Royal Geographical Society by G. R. Crone, with the assistance of R. A. Skelton and Helen Wallis from the British Museum Map Room. The speakers present came from Belgium (1), Canada (1), France (3), Ireland (2), the Netherlands (1), Portugal (1), the UK (3), and the USA (5); overall, fifty-eight people attended. Crone revealed his reasons for organizing the symposium in the final session, an open discussion of the “present state and future prospects” of map history. Thirty years previously, he argued, Edward Lynam in the British Museum and Edward Heawood in the Royal Geographical Society had labored almost alone on map history in Britain. Yet, Crone continued, the considerable post-war growth in British map historians had not been matched by any increase in intellectual standards. What the field needed, and what Crone hoped to stimulate with the symposium, was a more academic character (Crone, Skelton, and Wallis 1967).

The symposium was a success, and many of the papers were published in Imago Mundi, edited by Skelton, which had been published in Britain since Leo Bagrow’s death in 1957. In fact, Crone, Skelton, and Wallis promptly organized a second, now stand-alone symposium in 1967, under the aegis of Imago Mundi, Ltd., of which Crone and Skelton were directors (Harley 1968). The two London conferences were retroactively claimed as the first two International Conferences on the History of Cartography, when Imago Mundi, Ltd., convened what it called the third ICHC in Brussels in 1969. The biennial meetings of the ICHC have subsequently served as an institutional anchor for all kinds of map historians (Sims and Van der Krogt 1995).

The History of Cartography

The International Conferences on the History of Cartography were essential in growing the field of map history by making new and essential international connections [fig. 13]. In particular, in 1969, the third ICHC in Brussels saw the first meeting in person of David Woodward, just hired as the first map curator at the Newberry Library in Chicago, and Brian Harley, then working as an acquisition’s editor for David & Charles publishers, in Newton Abbot, Devon. (To be honest, it was not much of an international encounter, as the British-born Woodward had emigrated to the USA in 1964.) The two men hit it off, not least over their shared desire for the field of map history to become more academically sound.

Figure 13. Map historians at the 1989 International Conference on the History of Cartography, held in Amsterdam. Pictured during the poster session, on 28 June 1989, were David Woodward (USA, left) talking to Bob Karrow (USA), Eila Campbell (UK), someone who might be Ferjan Ormeling (Netherlands), and Josef Babicz (Poland, right). Photo by Peter van der Krogt, used with permission.

Eventually, Woodward and Harley agreed in 1977 to collaborate on a four-volume History of Cartography. Their intent was to use the History to lay a new foundation for the field by assessing what was known about mapmaking in the past (Edney 2015). They could not have even begun to think of such an endeavor without the connections that they made with the international field of map historians through the ICHCs. While broadly knowledgeable, they would not themselves be able to write about many specific topics and subjects. The remarkable thing about the History—what makes the series so different from a single-author monograph—has been its reliance on the international community of scholars who have combed the literature in multiple languages to provide the necessary detailed information and variant perspectives; thus, Cartography in the Nineteenth Century has 408 entries written by 179 scholars working in 29 different countries. Conversely, the History has been an avenue to spread an academic perspective through the field. As a result, the character of the ICHC has changed significantly over the decades!

It has not been a straight line from Simon Lefebvre and the transnational military engineers of the eighteenth century to the volumes of The History of Cartography, but the trajectory has been only slightly curved! Mapmaking inevitably became ever more international in its organizations and collaborations in order to map the entire world. The study of maps and their history similarly internationalized by necessity, in part to attain the needed perspective, in part to distribute the labor, effort, and cost to make map history feasible.

Matthew Edney


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