One reason for the growth of medieval towns was the principle of "stadtluft macht frei," or "town air makes you free," which meant

Stadtluft macht frei is a popular medieval German saying that literally means "the air of the city confers freedom". It synthesizes a phenomenon that several historians have identified in medieval Europe, due to the fact that many European cities were inhabited by free citizens, the bourgeoisie, in contrast to the surrounding agrarian zones, where the servants were under the feudal control of landowning families of the nobility.

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