The Four-Class System

To preserve Mongol nobles' rule over the Han and other peoples, the Yuan rulers pursued a policy of ethnic division and discrimination, and society gradually formed four classes: Mongols, Semu, Han and Southerners, known as the "four-class system". The first class was the Mongols, the ruling people of the Yuan, who enjoyed many privileges. The second was the "Semu", mainly the Tanguts (Xixia), Uyghurs, Huihui and people of Central Asian, West Asian, European and other origins, who had submitted early and helped the Mongols rule, and ranked just below the Mongols. The third was the "Han", meaning Han people formerly under the Jin north of the Huai River, plus Khitans, Jurchens, Koreans and others. The fourth was the "Southerners", broadly the Han and other peoples formerly under the Southern Song, who were conquered last by the Yuan and ranked lowest. The four classes were treated unequally in politics, economy and law. Politically, important posts at the center and in the localities, and the supervising office of darughachi in each place, were generally held by Mongols, next by Semu, while Han and Southerners could rarely hold major posts. In the civil service examinations, Mongols and Semu sat separate papers from Han and Southerners, with easier questions but the same number of places. Legally, a Mongol who killed a Han Chinese was only sentenced to military service and made to pay burial money, while a Han who killed a Mongol was put to death; Han and Southerners were also forbidden to keep weapons privately or to assemble and form societies. The system aggravated ethnic and social conflicts and was one of the important reasons the Yuan's rule was unstable and ended in under a hundred years.