Cologne around 1500 (1493) Cologne was the most important city of northwestern Germany, the seat of an elector-archbishop, and an important trading post for goods from all over Europe. Around 1500, it had a population of around 40,000, and was the largest German-speaking city. During the Reformation, it was the only northern free city that remained Catholic. Woodcut by Michael Wohlgemut, Liber Chronicarum, 1493, pp. 90b-91a.