The chungin were the upper middle class of the Joseon Dynasty in medieval and early modern Korean society. This privileged class of commoners consisted of a small group of petty bureaucrats and other highly educated skilled workers whose technical and administrative skills enabled the yangban and the royal family to rule the lower classes. Chungin were the lifeblood of the Korean Confucian agrarian bureaucracy, on whom the upper classes depended on to maintain their vice-like hold on the people. Their traditions and habits are the forerunners of the modern Korean administrative systems in both North and South Korea.