After the rule of Wenjing in the Western Han Dynasty, there was a long period of peace and many disadvantages. Internally, the princes were in power, threatening the central government, plundering and exploiting the people. Externally, the Xiongnu repeatedly killed and plundered the Han people, but the court was unable to attack.After Liu Che, Emperor Wu of the Han Dynasty, accumulated strength to start reforms, he adopted Dong Zhongshu's policy to unify his thoughts, used his father Yan Li to push forward orders, and ordered Sang Hongyang to carry out economic reforms such as salt, iron and currency systems, strengthen centralization, eliminate internal troubles, and increase national strength.The number increased greatly; Zhang Qian, Wei Qing, Huo Qubing and others, with the support of Liu Che, also made friends and attacked, united good friends, attacked the invading enemies, and promoted the prestige of the Han Dynasty.Through a series of institutional reforms, Liu Che consolidated the unified Chinese civilization and led the Western Han Dynasty to its peak.