It is a study focused specifically on the origine and evolution of Liao Yang Province, that one of the maximum local province(xing-sheng 行省) in the Mongol government of China in the thirteenth and fourteenth centuries. xing-sheng was one of a number of administrative innovationgs that the Mongols introduced into China. By February, 1211, preparationgs for the campaign were nearly complete and Chings Khan, who was encamped by the river Kerulen, sent his son-in-law, the Khongrad Tokuchar, with 2,000 men to mount guard on the western border. The army formed the Central and Left-wing armies and the Rigty-wing. Leading the former with CHingis himself were Mukhali, general-in-chief of the Left-wing army, Jebe, Subudei, Juchi Khassar and Tului. In command of the other were the princes Juchi, Ugedei. Beside these famous captains there were three others who particularly distinguished themselves in the war: a brothers Yeh-lü Akhai and Yeh-lü Tukha. Since both were well acquainted with the country north of the Great Wall. Early on, while the Mongols were still making their great conquests, Only the armed han ren shi hou(漢人世候) were unsalaried appointees with hereditary rights to the office who were charged by the khan or some other Mongol leader with one or more of a range of local tasks in conquered areas. So the military and civilian duties were undifferentiated during the years of the conquest of North Chiana, as is reflected in titles such as 'myriarch(wan-hu 萬戶)', 'du xing sheng(都行省)' etc. Before Ögödei's reign, there in conquered areas did not present a valid rule. Early in 1230s, shi lu zheng shou ke shui suo (10路徵收課稅所)was established, proposed by Yeh-lü chucai. One of these ten lu, peking-lu(北京路) was the administrative of northeast areas. Later it developed into larger organizations, liaoyang xingsheng(遼陽行省). From the time of Qubilai, the Mongols' conquests in China were, at least from the chinese point of view, "normalized" into the Yuan dynasty, and the Province were transformed in the process. By 1279, Qubilai and the Mongols had crushed the remnants of the Sung dynasty. It brought the remarkable improvement of local governance organizations. In 1284, after suppression of Nayan's rebellion, In Manchuria had formally established the Lioa Yang Province. About the seat of this province, this works proved that located in yi chou(懿州) since 1287. It revealing the nature of the provice.