An Analysis of the Causes of the Difference Between Dai Calendar and Lunar Calendar

Dai calendar is a calendar which mixed with the solar calendar and lunar calendar and forming its own system. Using the method of the Celestical Stems and the Terrestrial Branches to record days and years is an important part of Dai calendar, which have many relations with Han calendar and keep the pronounciation of ancient Chinese and succeed the custom of calling “mother”and “son”. The causes of this have not came to a pleased conclusion in some former discussions. Therefore, a new cause is derived in this paper from the migration history of the ancestor of Dai nationalities that the contents metioned above in Dai calendar were brought by their ancestors when their ancestors moved from the centre area of China to the area of Yunnan province where they are living today.