Medieval society was transformed by trade and “burgers.”
In medieval societies, the most widespread result of the revival of trade and urban life was the slow decay of federalisms and its inherent lack of loyalty and the infighting it promoted. Because of the increase in the power of the kings, countrywide courts were established that allowed the spread of “real” justice rather than piecemeal justice handed out by the local Baron. Increases in trade allowed for the creation of a money economy which promoted both the urban life and trade with other countries which increased the flow of ideas into Europe.
The developments of urban towns also created a new class of people — the burgers (from the German word Burg or Fortress) — who were entirely outside the feudal system. This gave them the power to change society. The burgers gained charters from the kings which they then used to free themselves from the remaining influences of the feudal system and allowed them to govern themselves which greatly increased individual freedoms. Because trade centered around the urban center, the cities themselves accumulated large amounts of money which were then used to build universities and cathedrals.
As a result of these developments the old systems such as feudalism, knights, barons, and feudal contracts were undermined and new systems grew to replace them — universities, guilds, cities, trade, and cathedrals.