Si Inthrathit was the first king of the Sukhothai Kingdom, a historical polity in what is now Thailand. He reigned from 1238 until around 1270 and is credited as the founder of the Phra Ruang dynasty,
Statue of Si Inthrathit, Sawankhalok District, Sukhothai Province, Thailand
Ramkhamhaeng, commonly known as Pho Khun Ramkhamhaeng the Great, was the third king of the Phra Ruang dynasty, ruling the Sukhothai Kingdom—a historical polity in what is now Thailand—from 1279 to 129
Si Inthrathit
…at a young age, and the second was named Ban Mueang. His third son defeated a Khmer prince on elephants in mounted combat; he named this youngest son Ram Khamhaeng (Rama the Bold) in tribute to the feat. Si Inthrathit died around 1270, and was succeeded by his son Ban Mueang. Princess Maha Chakri Sirindhorn…
Statue of King Ramkhamhaeng the Great, Sukhothai Historical Park, Sukhothai Province, Thailand
The three kings monument in Chiang Mai: King Ngam Muang of Phayao (left), King Mangrai of Lan Na (center), and King Ramkhamhaeng of Sukhothai (right).
Ramkhamhaeng stele, Bangkok National Museum