First of all, as far as its political system is concerned, Qin Shihuang established a centralized system, stipulated that the emperor was the supreme ruler, set up three officials and nine ministers under the emperor, abolished the previous enfeoffment system in various places, and promoted the county system. At the same time, it has improved the system of local administrative institutions and constituted a new and strict administrative system. It enabled the emperor's will to reach all parts of the country and strengthened the emperor's dominant position.
Secondly, in terms of economy and culture, Qin Shihuang unified the laws, writing, currency and weights and measures of the whole country. Abolish the original currency and characters of various countries and order the unified standards formulated by Shang Yang to be implemented throughout the country. It has realized the smooth circulation of material resources in various regions of the country and promoted the people's sense of identity with the Qin Dynasty.
In addition, the unity of culture has a great influence on the ideological development of later generations. In particular, Qin Shihuang's thought of great unification ensures that future generations will be divided no matter what, and the ultimate goal is great unification.
There is also the sphere of influence. After Qin Shihuang unified the six countries, he immediately began to crusade against the Huns. Qin Shihuang sent Meng Tian to recover the Hetao area and build the Great Wall of Wan Li, which consolidated the defense in the north and accelerated the economic development in the north. But the most important thing is to expand the territory and lay the foundation for the future development of China.
Judging from the results, the unification of the Qin Dynasty is an inevitable trend of historical development. Although it did harm to the development of China during and after reunification, it still brought historical progress and necessary conditions for the development of some fields. It can be said that Qin Shihuang's unification of the six countries is of great significance to the development of China's history and modernity, and also has a far-reaching impact on China's feudal society.