Why is Confucianism the mainstream of traditional culture in China?

Confucianism can become the mainstream of traditional culture in China for three reasons.

First, Confucianism caters to the needs of rule. Confucianism preaches social order, respects order and requires people to abide by the etiquette system. These just cater to the needs of the rulers to maintain social stability, and make Confucianism rise to the position of orthodox thought and become an official document.

Second, Confucianism has a broad mass base. Benevolence and propriety, the core of Confucianism, are in line with the traditional concepts of ancient Chinese people, very close to the people, easily accepted by the people, and have a broad mass base.

Third, the continuous improvement of Confucianism itself. Confucianism is tolerant. Although it is constantly impacted by other thoughts in the process of development, it can integrate the connotations of various thoughts into its own thoughts and make it better adapt to the times, such as the "three religions merging Confucianism" in the Song Dynasty.