Prosperous period of Lanna Kingdom was recorded with a long history for more than 700 years ago. The kingdom consisted of 8 provinces, namely Chiang Mai, Chiang Rai, Phayao, Phrae, Nan, Lampang, Lamphun and Mae Hong Son. Astronomical records of events and calculations were found in old local texts, mostly written in palmleaves or paper and occasionally on stone’s inscription.

The people of Lanna were interested in the sun, moon and planets for practical reasons, mainly calendar making and astrology. The system of Lanna’s calendar was mainly under Indian influence, especially from “Surya Siddhanta”, calculations have been significantly simplified without losing its correctness. Many Lanna’s chronicles had also recorded observations of astronomical events ie : solar eclipse, lunar eclipse and conjunction of planets. However, they tended to explain those incomprehensible phenomena with ideas taken from spiritual life or their religions.