There are several childhood lessons that I trace back to dinners at Outback Steakhouse: the deliciousness of cheese fries, the inconvenience of being in the middle of a wraparound booth, and the historical contingency of North as "up" on maps.

Who started using the NESW arrangement that is virtually omnipresent on maps today? Was it due to the fact that civilization as we now know it developed in the Northern hemisphere? (Incidentally, that's why clocks run clockwise--a sundial in the Southern hemisphere goes the other way around.)

That doesn't appear to be the case according to Nick Danforth, who recently took on this question at al-Jazeera America (via Flowing Data):

There is nothing inevitable or intrinsically correct — not in geographic, cartographic or even philosophical terms — about the north being represented as up, because up on a map is a human construction, not a natural one. Some of the very earliest Egyptian maps show the south as up, presumably equating the Nile’s northward flow with the force of gravity. And there was a long stretch in the medieval era when most European maps were drawn with the east on the top. If there was any doubt about this move’s religious significance, they eliminated it with their maps’ pious illustrations, whether of Adam and Eve or Christ enthroned. In the same period, Arab map makers often drew maps with the south facing up, possibly because this was how the Chinese did it.

So who started putting North up top? According to Danforth, that was Ptolemy:

[He] was a Hellenic cartographer from Egypt whose work in the second century A.D. laid out a systematic approach to mapping the world, complete with intersecting lines of longitude and latitude on a half-eaten-doughnut-shaped projection that reflected the curvature of the earth. The cartographers who made the first big, beautiful maps of the entire world, Old and New — men like Gerardus MercatorHenricus Martellus Germanus and Martin Waldseemuller — were obsessed with Ptolemy. They turned out copies of Ptolemy’s Geography on the newly invented printing press, put his portrait in the corners of their maps and used his writings to fill in places they had never been, even as their own discoveries were revealing the limitations of his work.

map_projectionsPtolemy probably had his reasons, but they are lost to history. As Danforth concludes, "The orientation of our maps, like so many other features of the modern world, arose from the interplay of chance, technology and politics in a way that defies our desire to impose easy or satisfying narratives." Yet another example of a micro-institution that rules our world.