In brief, the legend tells that
King Singhanti migrated with his followers from the city of Rājagṛha in Jambudvīpa (India). Together with local inhabitants, he founded a kingdom called
Nagabhandu Singhanti Nakhon (present-day Chiang Saen, Chiang Rai Province), making Chiang Saen the royal capital. The realm later expanded widely—eastward from the region of present-day Tonkin in Vietnam to the
Salween River and the
Shan State of
Myanmar, and northward from
Nong Sa in
Yunnan (China) down to the upper basin of the
Chao Phraya River. During the reign of
King Phangkharat, the Yonok–Chiang Saen Kingdom was invaded by the Khmer, forcing the people to move and establish a new city at Wiang Si Thong on the bank of the Mae Sai River. Later,
King Phrom Maharat, the royal son, successfully expelled the Khmer and invited King Phangkharat to return to rule Chiang Saen. King Phrom Maharat then led settlers to found Chai Prakan to the south of Chiang Saen as a frontier city to guard against further Khmer attacks. A long-standing debate concerns the dating in the legend, since the handwritten manuscripts were copied many times and spread widely, leading to errors. Three different eras of reckoning are mentioned—“Ancient Era,” “Second Era,” and “Third Era”—without clear explanation, causing chronological confusion. Scholars generally identify the Ancient Era as the
Anjana Era (148 years earlier than the Buddhist Era), the Second Era as the Buddhist Era itself (counted from the Buddha’s Parinibbāna), and the Third Era as the Great Era (621 years later than the Buddhist Era). ==References==