What are the main cultural factors that affect the folk customs of traditional festivals in China?

There are many reasons for the formation of folk customs, which are closely related to the cultural character and historical accumulation of a nation, as well as the physical geography and regional cultural characteristics of a certain area. However, I always feel that folk customs cannot be separated from the core of faith. There are differences in local customs, many of which stem from differences in folk beliefs. Only with the support of faith can every folk custom have a sense of texture.