Why do maps always show the north as being up? For those who don’t just take it for granted, the common answer is that Europeans made the maps, and they wanted to be on top. But there’s really no good reason for the north to claim top-notch cartographic real estate over any other bearing, as an examination of old maps from different places and historical periods can confirm.

The profound arbitrariness of our current cartographic conventions was made evident by McArthur’s Universal Corrective Map, an iconic upside-down view of the world that recently celebrated its 25th anniversary. Launched by Stuart McArthur, who was born in Melbourne, Australia, on Jan. 26, 1979 (Australia Day, naturally), this map is supposed to challenge our casual acceptance of white, European perspectives as global norms. But seen today with the title “Australia: No Longer Down Under,” it’s hard not to wonder why the upside-down map, for all its subversiveness, wasn’t called “Botswana: Back Where It Belongs” or perhaps “Paraguay Paramount!”

The McArthur map also makes us wonder why we are so quick to assume that Northern Europeans were the ones who invented the modern map — and decided which way to hold it — in the first place. As is so often the case, our eagerness to invoke Eurocentrism displays a certain bias of its own, since in fact, the north’s elite cartographic status owes more to Byzantine monks and Majorcan Jews than it does to any Englishman.

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 at least, 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....