Sukhothai Kingdom’s location: North-central part of Thailand, on the river banks of Yom River
In the beginning of the 13th century, Thais gradually began to liberate themselves from the control of the Khmer and Mon. They established the first somewhat minor city-states in the North such as Phayao and Lanna (near Lamphun), Chiang Saen and Sukhotai.
In 1238 CE, two Thai chieftains (or ‘เจ้าเมือง’ ), Pho Khun Pha Mueang and Pho Khun Bang Klang Hao (or Pho Khun Sri Indraditya) revolted against the Khmer Empire and declared independence from this empire. Therefore, the official Thai history traditionally regards the city-state of Sukhothai as the first kingdom of Thai nation.
Sukhothai was ruled by nine kings of The Phra Ruang Dynasty(1238 - 1438) :
Pho Khun Sri Intarathitya: 1238 – 1257 (or King Sri Indraditya)
Pho Khun Pa Muang: 1257 - 1277
Pho Khun Ramkhamhaeng Maharat: 1279 - 1317
Phaya Loethai: 1317 – 1347
Phaya Nguanamthom 1323-1347
Phaya Lithai or King Thammaracha I: 1347 - 1374
Phaya leuthai or King Thammaracha II: 1374 - 1399
Phaya Saileuthai or King Thammaracha III : 1399 - 1419
Phaya Borommapan or King Thammaracha IV: 1419 - 1446
Pho Khun Sri Nao Nam Thom (พ่อขุนศรีนาวนัมถม) was the first ruler of areas that covered Si Sat Chanalai (or เมืองเชลียง), Sraluang-songquare (or เมืองสรลวงสองแคว), and Sukhothai.
After Pho Khun Si Nao Nam Thom died, a Khmer warrior named Khom Sabat Khlon Lamphong besieged the town. Pho Khun Pha Muang, a ruler of Muang Rat and a son of Pho Khun Si Nao Nam Thom, and his friend Pho Khun Bang Klang Hao, fought against the Khmers and won them.
Pho Khun Pha Muang then gave Pho Khun Bang Klang Hao the Sword of Victory (พระขรรค์ไชยศรี) and consecrated him as “Pho Khun Si Indraditya”, a ruler of Sukhothai and the founder of the Phra Ruang Dynasty.