1. You asked about the implementation background ... The Song Dynasty, whether it was the Southern Song Dynasty or the Northern Song Dynasty, was a state of confrontation. The rulers of Northern Song Dynasty, Liao Dynasty, Xixia Dynasty, Southern Song Dynasty, Jin Dynasty and Song Dynasty adopted peaceful means and paid a large number of tributes to neighboring countries every year. The establishment of the Yuan Dynasty was an independent and unified country, which consolidated national unity politically and ensured centralization in the administrative system. This is a great change in China's administrative system, which has a great influence on later generations.
2. When I was in Yuan Shizu, I started to establish China Book Province. During the period from the unification of China to the first year, Zhongshu Province was established in various places as the agency of Zhongshu Province. Later, it gradually became a fixed local administrative agency, responsible for military and political affairs within its jurisdiction. The provincial system is to set up the state affairs of Premier China in the central government, with the Privy Council in charge of military affairs and the Yushitai in charge of supervision; In the local area, there is a provincial secretariat, and each province has a prime minister who is in charge of the province's military and political affairs. It not only lightened the burden on the king, but also consolidated Yuan's rule.
3. 1. The duality of provinces is conducive to centralization. At first, the provinces in Yuan Dynasty were only temporary central institutions, but in the later period of Kublai Khan's rule in Yuan Shizu, the provinces basically took shape and turned into permanent local administrative regions. However, even after the provinces are completely stereotyped and localized, it still has the nature of a central institution or a branch of a central province. "The evolution of provinces into the highest local government is only a basic aspect of its nature"; "Even after the completion of the above evolution, the provinces still retain some original attributes of imperial institutions for a long time, and ... they are not pure local officials" (Li Zhian's Study on the System of Provinces), which makes the provinces have the characteristics of duality, which is not available in the relationship between the central and local administrative regions in other dynasties. This feature makes the provinces not only restricted by the central government, but also serve the rule of the Yuan Dynasty.
2. The effective control of the provinces by the central government is conducive to centralization. "Although military affairs are heavy, they are all led", but in the actual operation process, they are all restrained and restricted by the central authorities, so "there is a town of governors, but there is no power of governors" (Zhao Tianlin cited "Financial Management" Volume 273). For example, in terms of personnel rights, the selection of local officials in the Yuan Dynasty was mainly handled by the Central Book Province and the Official Department. There were few provincial officials, and they had the right to interpret and adjust, which was far less than that of local officials in the Han and Tang Dynasties. In terms of finance, the provinces only acted as a tool for the court to concentrate fiscal revenue. Provinces must implement a disparity ratio of 70% to 30% for the central and local governments to retain, and they are also obliged to follow the orders of the imperial court and allocate extra funds to make up for the shortage of central fiscal tax expenditure. Militarily, the provinces cannot exercise military power independently, and the military power lies in the Central Privy Council. In the judicial aspect, the imperial court has also formulated strict rules and regulations for the provinces, which cannot be exceeded.
3. The mutual restriction of power within provinces is conducive to centralization. In the Yuan Dynasty, the provincial officials were in charge of the group, and the meeting system was implemented, that is, through the collective meeting of provincial officials, officials had both responsibilities, coordination and constraints, and each provincial official could not exercise his power independently, but was assisted or restricted by other colleagues. At the same time, the central government has also established a special mechanism to supervise the provinces and prevent them from using their power. For example, the establishment of Yushitai in Jiangnan and Shaanxi, and the local supervision network composed of 22 low-cost visitors were all pioneering works of local supervision in Yuan Dynasty. In the Yuan Dynasty, most provincial, imperial and incorruptible inspection departments were in a state of opposition and mutual attack to some extent, which effectively played a role in strengthening centralization.
4. The ownership of provincial power is conducive to centralization. As an effective tool of state rule, the provincial officials in Yuan Dynasty were mainly controlled by Mongols and Semu people. Take the most critical and sensitive military force as an example. Only provincial officials above Pingzhang are allowed to hold military power, and officials above Pingzhang are not allowed to be held by Han people. Usually, they can only be held by Mongols and Semu nobles. "Although they put their hopes on the Han people, they suppressed them" (Yuan Shi, Volume 186, Biography of Cheng Zun). Because as a governor with different ethnic identities and cultural backgrounds, even if he is in power, it is hard to imagine that he will incite the Han nationality or be able to incite the Han nationality to split. In a word, the national color of the Yuan Dynasty's rule largely determined that the provinces mainly acted on behalf of the will and interests of the imperial court, and became an effective tool for the central government to control places, rather than the opposite of the central government. Therefore, when we understand the provincial system in Yuan Dynasty, we should not explain it completely from the natural trend of the social and historical development of the Han nationality, but from the special historical environment at that time and the unique ruling consciousness of the Mongolian ruling group. This is why the provincial system in the Yuan Dynasty played a role in consolidating the rule, while Zhu Yuanzhang was still divided into three parts in the early Ming Dynasty.
5. Dividing provinces is conducive to centralization. Since Qin and Han dynasties, the administrative divisions of soil fertility have been determined by the natural boundaries of mountains and rivers or historical traditions, and the natural attributes of administrative districts have a strong trend of economic and cultural integration, which is prone to separatist situation. Since the Yuan Dynasty, the division of provinces is mainly aimed at the central military control, adopting the principle of "jagged teeth", arbitrarily combining areas with great differences in natural environment into a provincial administrative region, weakening the local economic and cultural identity, and artificially creating a situation of jagged teeth and controlling the south in the north. In this way, provincial officials lost the geographical conditions for taking risks and defending, and the court was easier to control. For example, Hanzhong, south of Qinling Mountains, was placed in Shaanxi Province, which opened the northward entrance of Sichuan Basin. This method of dividing administrative regions naturally strengthens centralization and objectively promotes economic, political and cultural exchanges between people of all ethnic groups.
To sum up, although the provincial system in Yuan Dynasty really contradicted the idea of increasing centralization of Han society since Tang and Song Dynasties, as a product of social development in Yuan Dynasty, it still played its purpose of strengthening centralization and consolidating rule, and also had a far-reaching impact on the political system of later generations, especially on local administrative divisions.
4. Strengthening the central power with strength and weakness has also removed many useful things. The development direction is too monotonous, and there are advantages and disadvantages without breadth.