Editing Sukhothai Kingdom (section)

===Expansion under Ram Khamhaeng===
[[File:Thai - Seated Buddha in "Maravijaya" - Walters 542520.jpg|thumb|A [[Maravijaya attitude|Māravijaya]] [[Gautama Buddha|Buddha]] from Sukhothai, dated to the second half of the 13th century, at the [[Walters Art Museum]].<ref>{{cite web|title=Seated Buddha in "Maravijaya"|url=http://art.thewalters.org/detail/15634|publisher=[[The Walters Art Museum]]}}</ref>]]
In 1270, Si Inthrathit died and was succeeded by his son [[Ban Mueang]]. At the end of Ban Mueang's reign, he was succeeded by his brother [[Ram Khamhaeng|Ram Khamhaeng the Great]]; both expanded Sukhothai beyond the borders established by their father. To the south, Ram Khamhaeng subjugated the [[Mandala (political model)|mandala]] kingdoms of [[Suvarnabhumi]] (likely present-day [[Suphan Buri]]) and [[Tambralinga]] (present-day [[Nakhon Si Thammarat]]). Through the acquisition of Tambralinga, Ram Khamhaeng is said to have adopted [[Theravada|Theravada Buddhism]] as the state religion of Sukhothai; the accuracy of these claims by traditional historians is disputed.<ref name=thanit/>{{rp|3–4}} 

To the north, Ram Khamhaeng placed [[Phrae]] and [[Muang Sua]] (present-day [[Luang Prabang]], [[Laos]]), among other mandala city-states, [[tributary state|under tribute]]. To the west, Ram Khamhaeng helped assist the [[Mon people]] under [[Wareru]] (who is said to have eloped with Ram Khamhaeng's daughter) in their rebellion against [[Pagan Empire|Pagan]] control, and Wareru would establish a kingdom at [[Mottama|Martaban]], the predecessor to [[Hanthawaddy Kingdom|Hanthawaddy]] (present-day [[Bago, Myanmar|Bago]], [[Myanmar]]). Martaban is traditionally considered a tributary state of Sukhothai, but such Sukhothai domination may not have extended that far.<ref name=thanit/>{{rp|4}} This policy of gathering vassals allowed him to claim suzerainty from [[Luang Prabang]] in the north to [[Nakhon Si Thammarat|Nakhon Sithammarat]] in the south, from [[Vientiane Prefecture|Vientiane]] in the east and from [[Bago, Myanmar|Pegu]] in the west. His success can be mainly attributed to his battlefield reputation. When he died in 1298, the far-flung bonds of vassalage that he established quickly disintegrated as his successors could not command the same level of authority.<ref>{{Cite book |last=Starling |first=Nicholas |title=The Cambridge History of Southeast Asia Volume 1 Part 1 |publisher=Cambridge University Press |year=1992 |pages=169 |language=en}}</ref> 

With regard to religion and culture, Ram Khamhaeng requested monks from Sri Thamnakorn to propagate [[Theravada Buddhism]] in Sukhothai. In 1283, the [[Sukhothai script]] was likely invented by Ram Khamhaeng; the earliest evidence of this ancient Thai writing is seen in the [[Ram Khamhaeng Inscription]], discovered by [[Mongkut]] (Rama IV) nearly six centuries later. The script later evolved into the [[Thai script|modern Thai script]] of today.

It was also during this time that the first relations with [[Yuan dynasty|Yuan China]] were established and Sukhothai began sending trade missions to China. The well-known [[export good|exported good]] of Sukhothai was the [[Sangkhalok ceramic ware|sangkhalok ware]]. This was the only period in Thai history that Siam produced Chinese-style ceramics, and they fell out of use by the 14th century.