Gerardus Mercator: Why the 16th century Fleming cartographer is in the African Union’s crosshairs

The 55-member African Union (AU) has called for adoption of a world map that accurately displays the size of Africa, the world’s second-largest continent.

The bloc has backed the ‘Correct The Map’ campaign led by advocacy groups Africa No Filter and Speak Up Africa, according to Reuters. The campaign urges organisations to adopt the 2018 Equal Earth projection, which tries to reflect countries’ true sizes.

 The AU has also criticised the Mercator Projection, which has been popular with mapmakers for nearly half a millennium, but which according to the AU has presented a falsified and inaccurate image of Africa.

AU Commission deputy chairperson Selma Malika Haddadi told Reuters that “It might seem to be just a map, but in reality, it is not.”

She added that the Mercator Projection fostered a false impression that Africa was “marginal,” despite being the world’s second-largest continent by area, with over a billion people. Such stereotypes influence media, education and policy, she said.

The AU’s critique of the Mercator Projection is only the latest in a series of attacks against the projection which have particularly intensified since the last century.

But who was the man behind this unique method of mapmaking?

The cartographer from Flanders

“Gerardus Mercator (or Gerard de Cremer to give him his real Flemish name) was born on 5 March 1512 in Rupelmonde, near Antwerp, Flanders (Belgium), the seventh child of the shoemaker Hubertus de Cremer and his wife, Emerentia It is thought that Gijsbrecht de Cremer, an uncle and chaplain, provided educational and financial assistance to such a large family,” writes Carlos van Caiiwenherghe, Former Head of Hydrographic Service, Belgium, in his 2005 paper, Gerardus Mercator Rupelmundanus: Cartographer & Renaissance Man.

Mercator attended school in Hertogenbosch today in the Netherlands but then in the Duchy of Brabant, before graduating with a Master’s degree from University of Louvain (in today’s Belgium) in 1532.

He left “a conservative, doctrinaire Louvaine in 1533 or 1534 for the more liberal pastures of Antwerp, then a richly cultured city which was also the centre of typography in Western Europe”, writes van Caiiwenherghe.

A few years later, he returned to Louvain where he embarked on his career as a cartographer. It was the Age of Discovery. European seafarers fanned out in ships across the world’s oceans, looking for new lands. Mercator intended to “work with more practical people skilled in helping him to map a world awakened by numerous discoveries by mariners around the globe”, as per van Caiiwenherghe.

The Mercator Projection

Mercator hit upon a unique way to represent the planet earth, a sphere, as accurately as he could on a flat sheet of paper.

An article by University College Oxford describes the attempt: “Now called the Mercator projection, his system straightened out the meridian lines on a globe, meaning that land masses were stretched east-west, more prominently the further from the equator they are. To combat the way this deformed their shape, Mercator imposed a proportionate stretching along the north-south lines.”

It was in August 1569 that Mercator’s world map titled Nova et aucta orbis terrae descriptio ad usum navigantium emendate accommodate or “New and More Complete Representation of the Terrestrial Globe Properly Adapted for Use in Navigation” was published.

“The projection allows sailors to navigate following rhumb lines (or loxodromes), as these always appear on the map as straight lines, with the curvature of the earth taken into account. Mercator had found a way to transfer a 3D object onto a 2D plane,” notes the Oxford article.

However, it would take a few more decades before the Mercator Projection would actually become popular.

This happened after the Irish mathematician and cosmographer, Edward Wright (1558-1615) formulated the mathematical basis of the projection in his 1599 work, Certaine Errors in Navigation Detected and Corrected.

“This provided an explanation otherwise lacking in Mercator’s work. And so, it was only in 1630 that the Mercator projection began to be used on nautical charts accompanied by explanations in local languages,” notes van Caiiwenherghe.

Mercator died in Duisburg in the Holy Roman Empire (in today’s Germany) on December 2, 1594, aged 82.

Popularity, controversy and criticism

In The Mercator Projection: Its Uses, Misuses, and Its Association with Scientific Information and the Rise of Scientific Societies (2019), Michele Abee notes that “From 1569 to 1900, the Mercator Projection has had various uses, both valuable and ill-suited. Gerard Mercator successfully created a projection to solve a critical navigational problem at a time that western Europeans were sailing and exploring increasingly further away from known waters.”

By 1900, she adds, the projection “was well entrenched as a popular projection for general world reference or thematic maps, even though academic cartographers argued that it was ill suited for those purposes”.

It was in the 20th century though that the Mercator Projection faced a storm of controversy. That storm was brought about by a man called Arno Peters.

The German historian announced the Peters world map in 1974. He claimed it to be the most accurate representation of the world. On closer scrutiny though, it was found that Peters’ projection was similar to something developed a century earlier by Scotsman James Gall, although it was later proved that Peters had not plagiarised from Gall, as he was unaware of the latter’s work.

But Peters did something else.

Peters claimed that the Mercator projection distorted the relative sizes of landmasses, especially in higher latitudes, notes Jeremy Crampton from the Department of Geography, George Mason University, United States.

“Peters argued that this results in a relative increase in the size of ‘old world’ countries over ‘third world’ countries (e.g., African countries). Indeed, at the Bonn press conference, Peters went so far as to say that the Mercator projection “overvalues the white man and distorts the picture of the world to the advantage of the colonial masters of the time”,” Crampton writes in his 1994 paper, Cartography’s Defining Moment: The Peters Projection Controversy, 1974-1990.

According to Abee, this allegation by Peters that “the continued use of the Mercator Projection perpetuated a European bias of the nature of the world, or perhaps racism, as well as his marketing of what most practicing cartographers considered to be a highly flawed projection as the best alternative to the Mercator Projection, infuriated many cartographers and resulted in several cartographic societies formally condemning the use of the Peters Projection”.

It is this controversial aspect of the Mercator Projection that has now been picked up by the AU. As the Oxford article notes, Mercator’s system “maintains the angles and shapes of countries, but has the unfortunate effect of distorting the relative sizes of land masses, meaning Greenland looks similar in size to Africa, whereas it’s closer to the size of the Democratic Republic of the Congo”.

Crampton says that while the question of whether Peters was effective in promoting his ideology is a legitimate one, “what is no longer possible is to refuse to acknowledge that Peters is legitimate in having an ideological agenda. It has been this very refusal by the majority of cartographers that has given rise to the misunderstandings engendered by the two sides. The only way the sides could ever meet is by acknowledging the legitimacy of both agendas—the technical and the ideological”.

He cites the late US cartographer John P Snyder who concluded that even if cartographers dislike the Peters world map, it is “challenging them to offer better ones”. “The defining moment of the controversy has both illuminated the practice of cartography and given it a chance to redefine itself,” writes Crampton.