The Spring and Autumn Period and the Warring States Period is a period of great changes in the history of China. Combined with historical facts, this paper summarizes these changes and the reasons for them. Changes: (1) Economically, ironware and Niu Geng became popular, productivity increased rapidly, well-field system collapsed, feudal mode of production appeared, landlord class and peasant class formed, and independent craftsmen and businessmen appeared. Under the new production relations, workers' enthusiasm for production has been improved, agriculture and handicrafts have developed, commodities have been exchanged frequently, and various currencies have appeared, forming a commercial center.

(2) Politically, during the Spring and Autumn Period, the royal family declined and the great powers competed for hegemony. Some vassal ministers held power, showing the phenomenon of mutual restraint and chaos in the world. During the Warring States period, this situation further developed and a series of reform measures were taken. The autocratic county system centered on the king replaced the feudal system, and the military rank system replaced the historical system. The era when the slave owners and nobles enjoyed privileges from generation to generation in the Western Zhou Dynasty changed, and the trend of unification began to appear.

(3) Ideological and cultural aspects: the first great ideological liberation appeared in the history of our country. Old ideas have been impacted, people's attention has spread in the society, the situation of learning in the official has been broken, and private lectures have begun, forming a situation of "a hundred schools of thought contend". Science, technology and cultural education have also developed accordingly.

(4) Military aspect: frequent wars, constant wars for hegemony, and a series of military works.

Reason for change: Since the Spring and Autumn Period, the popularization of iron ware and Niu Geng has greatly improved productivity. The development of productive forces will certainly have an impact on production relations and superstructure. It also impacted the ruling order and concept at that time. This period is also a rare opening period in history, showing a lively and upward post-atmosphere, which will inevitably produce reactions in various fields.

This topic mainly examines students' ability to analyze, understand and summarize problems and grasp stage characteristics through social changes in the Spring and Autumn Period and the Warring States Period. The social changes in this period are fully discussed in textbooks, but they are scattered. When you answer, you must sum up the question from the aspects of politics, economy, ideology and culture, military affairs and ethnic relations. It is necessary to summarize the core content through a large number of historical facts. According to the viewpoint of productive forces and the social situation at that time, this paper analyzes the reasons leading to social changes.