1238 - Taking advantage of the weakening of the Khmer empire, two local Thai princes, Khun Bang Klang and Khun Pa Muang, both of them actually officials of the Khmer occupation government in Sayam (later, and until the present, Sukhothai) start a rebellion against the Khmers. Khan Lampong, a Cambodian General, tries to subdue the Thais but is defeated. Sukhothai thereby becomes a truly independent state. Khun Bang Klang is crowned King of Sukhothai under the title Sri Inthrathit. Khun Pa Muang is only given a major government post, far inferior to the reward of Khun Bang Klang. The reason for this is his marriage with a Khmer princess - a matter that casts doubt on his trustworthiness in the Thais?eyes. The Principality or Kingdom of Sukhothai grows rapidly in the following years - as a result of military conquest as well as rather diplomatic annexations of other Thai principalities formerly ruled by Khmers. These diplomatic annexations become possible because according to today’s knowledge, Sukhothai is an attractive state to join. It is much more liberal than most states of the time, knowing no slavery nor excessive taxation by the monarchy. Being a new kingdom, the rulers have not progressed on the typical path of becoming distant from their subjects. Kings are not considered god-kings as it had been under Khmer rule.
1254 - Kublai Khan, Mongolian ruler in central China conquers the Nanchao Kingdom, several hundred kilometers to the north in today’s southern China (see above). Great waves of Thai migrants flood Sukhothai from Yunnan enhancing Sukhothai’s population and power base.
1262 - Prince Mengrai of Nanchao, after having escaped the wrath of Kublai Khan, establishes the Lannatai Kingdom with himself as king. To serve as his capital, he founds the town of Chiang Rai. In the following years, he integrates several neighboring Thai principalities into his kingdom. Although relations with Sukhothai are cordial for the first decades and in spite of the fact that many former Nanchao subjects become citizens of Sukhothai, the two kingdoms do not unite. Lannatai will later first become an ally of the Burmese against the Thai Kingdom of Ayutthaya (Siam) and then be a Burmese vassal or integrated into Burma for several centuries. It is noticeable in present-day Thailand that, except in Chiang Mai and the utmost north of today’s Thailand, Thais have much less sentiments about the kingdom of Lannatai than about Sukhothai, even though the independent history of Lannatai is considerably longer than that of Sukhothai (a mere 140 years).
1279 - Ramkhamhaeng, the third of three sons of Sri Inthrathit becomes king of Sukhothai. He is however preceded on the throne by his elder brother Ban Muang (not to be confused with Prince Pa Muang who had joined Sri Inthrathit in overthrowing the Khmer rule). But there are no records on when Sri Inthrathit died or for how long Ban Muang ruled. As there are no records it was most probably an exceptionally peaceful time. This changes when Ramkhamhaeng ascends to the throne. In the following years Ramkhamhaeng’s armies conquer an area encompassing most of what is now Thailand plus the eastern part of what is today Burma plus almost the whole of the Malayan Peninsula.
Ethnically speaking, he ruled not only over Thais but also over Burmese, Mons and Shans in the west, Malays in the south and Khmers and Laotians (ethnically closely related to the Thais) in the east. As the relations between King Mengrai of Lannatai and King Ramkhamhaeng of Sukhothai have remained cordial, Ramkhamhaeng does not touch his northern neighbor. Impressing as they may be, Ramkhamhaeng’s military exploits are by far not his only achievement. He also creates the Thai alphabet that is basically still in use, codifies the law and conducts a reform of Buddhism practiced in his realm by establishing stricter rules for the behavior of monks. The Thai alphabet invented by him draws on Sanskrit and Pali (both languages of Indian origin) as well as the written languages of the Burmese and the Khmers, both of which are also Sanskrit and Pali based. But not only are the letters of neighboring languages used to provide for a written Thai language. Terms from Pali, Sanskrit and the immediate neighboring languages are also integrated into Thai (which otherwise is quite different from Burmese and the Khmer language). The development of the Thai language in southeast Asia, in spite of it’s origin in China, explains why a large number of Royal titles or religious designations are quite similar to those of the Khmer or Burmese (the Thais adopted Buddhism only in southeast Asia, not during their history in what is now south China where Buddhism arrived only at a time when the Thai majority had already migrated to southeast Asia).
