Singhanavati (Thai: สิงหนวัติ, RTGS: Singhanawat) was a Tai semi-legendary kingdom based along the Kok River in the Chiang Rai Basin in northern Thailand,[1] existed from 691 BCE to 638 CE.

[1]: 9  This migration legend was supported by a bronze drum found in the wetland near Chiang Saen that was probably the submerged Yonok city; the artifacts were also discovered scattered along the river basins from southern China, Mekong valley, and northwestern Vietnam.

[1]: 9  However, in the 2009 archaeological excavations performed by the Fine Arts Department of Thailand, no ancient structures dating before 545 CE were found in the area, [1]: 9  which was considered the period when the city was submerged below the Chiang Saen Lake due to an earthquake.

[9][10][11] Phrom also led the army went to suppress the King Khom troops as far as the territory of Chakangrao in the south,[9] along with establishing a new town in 396 to be an outpost to prevent enemy invasion in the old Umongasela area and renamed it Chai Prakan.

[13] His son Chaiyasiri, continued to rule Chai Prakan;[14] however, after the fall of Yonok, Chayasiri, along with many of his subjects, moved south to settle in the present-day Nakhon Thai, Phitsanulok Province.

[17] The survivors, led by Khun Lung, went east to settle at Vieng Prueksa [th] and the remaining principalities, which consisted of fourteen chiefdoms, formed the chamber to select new rulers.

Simon de la Loubère's record refers to the first Siamese king, named Phra Pathom Suriyathep Norathai Suvarna Bophit (Thai: พระปฐมสุริยเทพนรไทยสุวรรณบพิตร, Pra Poat honne sourittep-pennaratui sonanne bopitra).

Thus do they reckon 52 Kings in the space of 934 years, but not all of the same blood lineage.”[15][21][20][22] Through the Theravada, the relationships between the southern principality, Tambralinga, during the reign of Chandrabhanu (r.1230–1262) and the Siamese leaders in the north of the Kra Isthmus was speculated to have begun after the foundation of Phetburi (Pipeli).