Ramkhamhaeng

Ramkhamhaeng led military campaigns that expanded the Sukhothai Kingdom's territory to cover much of modern-day Thailand, including parts of Laos and Myanmar. His conquests made Sukhothai a dominant power in mainland Southeast Asia.

Ramkhamhaeng is traditionally credited with creating the Thai alphabet, as recorded on the Ramkhamhaeng Stele. The script was adapted from Khmer and Mon scripts, enabling the recording of Thai language and literature.

Ramkhamhaeng sent tributary missions to the Yuan Dynasty court of Kublai Khan, establishing diplomatic and trade relations. This brought Chinese influence and goods to Sukhothai.