Epidemics in the Middle Ages led to a significant decrease in the population. This brought about changes in feudal relations. Small artisans began to hire people. The fields that were sown with cereals turned into pasture for livestock. Taxes increased, and the boundaries between estates were blurred. In Europe, numerous riots and uprisings brutally suppressed led to the transition from feudal to rental relations in agriculture. The replacement of serfdom with a quitrent turned out to be a more progressive form economically.