The events of Yang Di, Song Taizu, Yuan Shizu and Ming Taizu emperors.

During his reign, he initiated the imperial examination system, built the Sui Grand Canal, built the East Capital and moved the capital to Luoyang, which had a great influence on later generations. However, frequent wars, such as personally conquering Tuyuhun and three levies of Koguryo, abused the people's power and led to an increase in people's frequency.

Song Taizu

During his reign, Zhao Kuangyin devoted himself to unifying the whole country. According to Prime Minister Zhao Pu's strategy of "South first and then North", he successively eliminated the southern separatist regimes such as Jingnan, Wuping, Houshu, Nanhan and Nantang, until his younger brother Song Taizong Zhao Guangyi was in office and wuyue, Zhang Quan and Beihan were eliminated, thus completing the great cause of reunifying the whole country. In the second year of Jianlong (96 1) and Kaibao (969), Zhao Kuangyin "released the military power by borrowing wine" twice, which relieved the military power of the imperial generals and local buffer regions and solved the self-sufficiency of local foot soldiers since the middle of the Tang Dynasty. Set up a "sealed pile warehouse" to store money, silk and cloth, so that the sixteen States given to Qidan by Shi Jingtang, the great-grandfather of the late Jin Dynasty, could be redeemed, but it did not succeed.

Ming Taizu

During Zhu Yuanzhang's reign, in view of the chaos at the end of Yuan Dynasty, he reformed all aspects, abolished the prime minister politically, set up a department to undertake propaganda and deployment, a department to punish judges and judges, and decentralized all command departments to further strengthen centralization, severely punish corrupt officials and punish illegal officials; Militarily, the system of health centers was implemented and the Northern Expedition was carried out. Economically, we have made great efforts to resettle land and army, build water conservancy projects, liberate handmaiden, reduce the tax burden, and send people to all parts of the country to survey land and check household registration. Culturally, we should pay close attention to education, advocate imperial examinations, and establish imperial academy to train talents. Strengthen overseas exchanges and restore China's suzerain status.