On a map, in 99% of the cases, the north is represented at the top. But this is only a convention, nothing forces us to do so! So, the question that burns your lips (and it is quite normal), is : WHY IS THE NORTH AT THE TOP OF THE MAP? Let's try to answer it
First of all, there is no rule concerning the reading direction of a map. A map is a flat object that represents a sphere, but the Earth has no top or bottom because it is a sphere. So any orientation is in fact a choice, not a necessity. Throughout history, maps are oriented in a lot of different directions: East, South, North... very rarely. West even if it happens. All this is done according to cultural, religious conventions... but not at all according to geography!
The idea was to put at the "top" of the map what the cartographer considered to be the most important, depending on the culture: Mecca, the sunrise, the North Star, Paradise, and so on (and so forth). So, for a long time and depending on the nationality, culture (and employer!) of the cartographer, the maps will be oriented a little randomly. There is no general convention, neither in the North nor anywhere.
# Ptolemy's North
Let's go back in time. Ancient cultures oriented themselves on an east-west axis (by observing the sun) or north-south (by observing the North Star). This is why the first authoritative projection, created by Ptolemy in his "Geography" (c. 150) is oriented north. (this decision is also surely due to the fact that it is at that time much easier to calculate latitudes than longitudes)
# The Orient
By the way, where does the word "orient" come from? Well, from the orient (Latin "oriens"), therefore from the East. For a long time, maps had the East as their summit. In medieval Europe, maps tended to be oriented to the East. These are the famous "mappa mundi", like the Hereford one for example, which divide the world in 3 parts. The same applies to the one in Ebstorf (c. 1230), also facing east. On the mappa mundi, the cartography reflects the faith, a whole host of religious places are placed on the map (the Garden of Eden for example), and Jerusalem is at the center of the map. East is the direction of the Holy Land for Europeans: facing east puts Jerusalem on top AND in the center.
# The South
At the same time, at the court of the king of Sicily, the rockstar geographer al-Idrissi produced superb maps of the known world... oriented to the South! The cartographic tradition of Islam has indeed a tendency to orient to the South. The idea is that 1. One should pray in the direction of Mecca and 2. In its initial phase of expansion, most of the communities that converted to Islam lived exactly north of Mecca. This led them to consider the Qibla to be located due south. Muslim cartographers therefore placed the south at the top of their maps
In short, East, North, South, there is something for everyone.
# Why North ?
So why is North at the top of the map? In his excellent book "Why North is Up: Map Conventions and where They Came from", Mick Ashworth identifies 3 factors: the compass, Ptolemy, and the Mercator map.
The compass came from China in the 12th century, Europeans rediscovered the work of Claudius Ptolemy around the 15th century and Gerard Mercator (that rockstar) created his world map in 1569. So, all this is not recent-recent, but not old-old either. The rediscovery of Ptolemy in Europe, which advocates putting the north up, combined with modern methods of navigation (based on compass readings that favor the north as a direction of reference) is the doublet that will orient all our maps to the north.
Add to that Mercator's map (1569): it was such a revolution for map navigation methods that it quickly became the authority, and since it put north at the top, it was difficult to change that for other cartographers without the risk of looking old. Most of the European maps of the world drawn up towards the end of the 15th and the beginning of the 16th century gradually replaced the orientation to the East with an orientation to the North.
One last thing, it is that it was necessary to homogenize the maps. The "discoveries", the navigation, the sharing of the world by the Europeans, all that required a pooling of cartographic knowledge, and it was necessary to agree. It was the north that won.
Today, all this is very well established and seems unsurpassable, even if in-vehicle mapping apps tend to completely ignore orientation, rotating the map so that it always stays in the direction of travel. You just have to press a button to reorient it. This is the future of cartography: map orientation. But the North remains the world convention for mapping.
# References
- Jules Grandin (2022) Pourquoi le nord est-il en haut des cartes