In the tenth century, Paris was a provincial town of weak political and economic importance. Still, under the kings of the Capetian dynasty who ruled France until 14 century, it becomes a significant, commercial, political, and religious center.
Most of the city was on the contemporary Seine river’s left bank, where stood the essential part of the Roman period city. Famous monasteries and leading universities were built in the Left Bank of the city. I
The right bank also began to develop as a significant urban area relatively early and was already very important in the 12th century. The Right Bank, where the ports, markets, artisans, and tradespeople were settled, became the commercial center of Paris.
With 80 thousand residents, Paris became in the 13th century the most populous city in Christian Europe. But, the 14th century brought darker times – the population of Paris was decreased by famine between 1315 and 1317 and by plague in 1349.
But around the 14th or 15th century, the population reached almost 250 thousand residents, making it the most populated city in all of Europe.
1422 map of Paris on top of today Paris
Overhead map from a 3D reconstruction of medieval Paris
The map above is based on the map of Paris by Truschet and Hoyau, published in 1553.