When did centralization of authority in China start?

Centralization of authority in China began to sprout and develop during the Spring and Autumn Period and the Warring States Period. During the Spring and Autumn Period and the Warring States Period, the decline of the Zhou Emperor and the war of the princes made the vassal states see the disadvantages of the enfeoffment system, gradually incorporated local forces and strengthened centralization. The reform of various countries in the Spring and Autumn Period and the Warring States Period was the official beginning of centralized system. Among them, Shang Yang's reform in Qin was representative.

Qin unified the six countries, marking the formal establishment of China and centralization of authority.