The Thai people moved into the area of modern Thailand during the 12th century and established their first independent kingdom at Sukhothai in 1238. King Ram Khamhaeng of Sukhothai set up a stone inscription in 1292 celebrating his life and commitment to the rule of law, good governance, economic freedom, bravery, filial piety and religious morality, which the inscription depicts as a model Buddhist state. The King Ram Khamhaeng Inscription was inscribed on the International Memory of the World Register in 2003.
The Inscription is of 114.5 centimetres high with four sides and topped by a quadrilateral pyramid. The first side has 35 lines, the second 35 lines, the third 27 lines and the fourth 27 lines. Each side is 35.5 centimetres wide. It is the oldest surviving writing in the Thai language and the Thai script, and as such, is central to Thai history and culture. The script used for writing Thai was amended from the pre-existing Khmer and Mon scripts, which in turn descend from Pallava scripts anciently used in India. This Inscription is believed to be close in date to the time when the Thai script reached its definitive form. The changes introduced into the older scripts to make it perfectly fitted for the writing of Thai suggest that the script was designed by some group of scholars, probably under instructions issued by King Ram Khamhaeng. The script shown on this Inscription is still used by the Thai peoples in Thailand, Vietnam and elsewhere.
As the foundation of Thai history and culture, and as evidence of the conscious establishment of a new writing script to write a language previously unwritten, the King Ram Khamhaeng Inscription has world significance.