Through thousands of years of Chinese history, numerous numbers of countries repeated to rise and fall, especially during 1200BCE and 220CE due to two periods of warring nations. In this period, there were long lasting nations such as Han, which controlled the eastern China for 400 years, to nations that collapsed all of a sudden, like Qin. Even though there were countless numbers of nations existed in this period, there were some unchanging factors: strong centralized government and existence of shi. However, they also had various change in politics over time, which is the variation of fundamental idea.
First of all, every major nation during period 1200BCE and 220CE, Zhou, Qin, Han, established centralized government. This is crucial for Chinese history in that it is hard to find nations that established centralized government before these nations. Throughout the world, there were some centralized nations such as the Roman Empire of Mediterranean region in this era. However, these nations differed in how they had established centralized government. Zhou was able to establish initial centralized government mainly by mandate of heaven, which is the concept of king having both power and responsibility for ruling the nation. Qin established strong centralized government based on powerful military and strict legalism. Han established the most concrete centralization among these countries because instead of vassals or aristocrats, government officials of Han were sent to rule the provinces. Moreover, unlike Qin, Han adopted Confucianism instead of strict legalism. These nations endeavored to establish centralized government because it had advantages to the decentralized government in that the politic was stabled and there was less possibility of rebellion. Although these nations differed in how they established centralized government, kings and emperors of these nations had strong power compared to former