In which dynasty did Mid-Autumn Festival become a fixed festival?

Mid-Autumn Festival has been a fixed festival since the Tang Dynasty.

Mid-Autumn Festival has a long history in China. Like other traditional festivals, Mid-Autumn Festival develops slowly and remains unchanged. Ancient emperors had the ritual of offering sacrifices to the sun in spring and the moon in autumn. As early as Zhou Li, there was a record of the word "Mid-Autumn Festival". Later, aristocratic scholars followed suit. During the Mid-Autumn Festival, they watch and worship the bright and round moon in the sky and place their feelings on it. This custom spread to the people and formed a traditional activity.

It was not until the Tang Dynasty that people paid more attention to this custom of offering sacrifices to the moon. The Book of the New Tang Dynasty (Volume 15) and Records of Rites and Music contain "Spring and Autumn Gifts and Wang Wucheng", and in the 19th year of Kaiyuan, Taigong Fu Shang Temple was set up with Sean. In the Mid-Spring and Mid-Autumn Festival, there are sacrifices, and the system of sacrificial music is like a text. " Mid-Autumn Festival has become a fixed festival. This festival prevailed in the Song Dynasty, and in the Ming and Qing Dynasties, it was as famous as New Year's Day and became one of the major festivals in China.