Chaliang Kingdom แคว้นเชลียง (Thai) Kwaen Chaliang
Late 10th century –1474
Chaliang Sukhothai Songkwae Kamphaeng Phet Ayutthaya Location of four northern cities (Chaliang marks as red pog), vassal states of the Ayutthaya Kingdom
Capital	Chaliang (before 13th cen.) Old Si Satchanalai (13th c.–1786) Si Satchanalai (1786–1894)
Monarch
• Unknown	Satchanalai (first)
• 1157–1182	Srinaonamthum [th]
Historical era	Post-classical era
• Establishment	Early 9th century
• Tambralinga annexed Lavo	927/928
• First mentioned in Chinese source	1001
• Formation of Sukhothai	1238
• Vassal of Ayutthaya	1378–1462
• Vassal of Lan Na	1462–1474
• Incorporated to Lan Na	1474
• Burmese rule over Lan Na	1558–1775
• Under Siam control	1776–1894
• Demoted to the city under Phitsanulok [th]	1894
Preceded by Succeeded by Lavo Dvaravati Lan Na Kingdom
Today part of	Thailand

Chaliang (Thai: เชลียง, Chinese: 程良) or Sawankhalok, later known as Si Satchanalai, was a political entity in the upper Chao Phraya Valley in central Thailand.^[1] It was founded in the late 10th century by uniting four regional chiefdoms^[2]: 7 and became part of the Dvaravati's Lavo.^{[1]: 32–33} In 1001, Chaliang was referred to as an independent kingdom Chéng Liáng in the Chinese text Song Shi.^{[3][1]: 28 [4]} The term San-lo (三濼) mentioned in Lingwai Daida in 1178^{[5]: 288, 290} was plausibly referred to the new Chaliang's center, Sawankhalok.^[1]: 8

Chaliang led by Srinaonamthum [th]^[6] expanded political influence to Sukhothai of Lavo^[1]: 4 in 1175.^[6] However, nobles of the Lavo faction revolted and recaptured Sukhothai in 1181,^[3] which caused Tai kings from Mueang Rad and Mueang Bang Yang to join forces and retake Sukhothai in 1238. This marked the formation of the Sukhothai Kingdom.^[1]: 4

During the Sukhothai era, Chaliang was comparable to and equal to Sukhothai, in which both cities were the capital.^{[1]: 25–26} However, after the Sukhothai Kingdom became the vassal of Ayutthaya, Chaliang lost its political influence^{[1]: 9–12} and was later demoted to the frontier city after Ayutthaya lost it to Lan Na in the 15th century.^[7]

The English term "Chaliang" is the romanization of the Thai word "เชลียง" per the Royal Thai General System of Transcription. The Thai word for the historical country was plausible a transliteration of the combination of two words: the Sanskrit word Chala (Sanskrit: जल) which means "water" and the Old Khmer word Wang (Old Khmer: វាង៑) which means "city". Together, the combined word can be interpreted as meaning "city of water," as the city is almost surrounded by the Yom River.^[8]

The region was inhabited since the Neolithic–Iron Ages.^[1]: 30 It then evolved into agricultural communities in the early 4th century and turned into complex societies around the 9th century.^{[1]: 29–32} Artifacts found in Chaliang-Si Satchanalai show that the communities engaged in trade with several Dvaravati polities, such as Si Mahosot [th] in the southeast, and Mueang Fa Daet Song Yang and Ban Mueang Fai (บ้านเมืองฝ้าย) in northeastern Thailand.^{[1]: 32–33} Chaliang, on the great bend of the Yom River, was likely inhabited by people who had migrated from the lower Chao Phraya basin, whereas Si Satchanalai, which was situated close to the base of the mountain and along the river, was probably of the people from the northern highlands.^{[1]: 33–34}

According to the Northern Chronicle [th], Chaliang was founded by a hermit, Satchanalai (สัชนาลัย), who united four surrounding chiefdoms and built moats and walls to define the city's boundaries.^{[1]: 37 [2]: 7} Its initial territory included Thung Yung [th] or Wiang Chao Ngo [th] to northeast, and met Sukhothai to the south.

The kingdom established relations with Tai's Chiang Saen in the late 10th century when the princess of King Supojarat married the King of Chiang Saen, Sri Thammasokkarat,^[2]: 18 and the son of them later enthroned the king of Chaliang.^[2]: 21 This marked the beginning of Tai influence over the Chao Phraya Valley, which had been devastated by the invasion of Tambralinga in the mid-10th century^{[9][10]: 23 [11]} and the destruction of Lavo by the Angkor in the early 11th century.^[12]

Initially, Chaliang was under Sukhothai, which itself was a trading hotspot of the Lavo Kingdom.^[13]: 3 At least in 1001, it was potentially ruled by the Tai as it was mentioned as an independent polity centered in Chéng Liáng (程良) in the 4th year of Xián Píng era 咸平 (1001 CE) in the Chinese Song Shi volume 489 section 248.^[3][1]: 28 It was said to be located 60 chéng (程) from the north of Tambralinga, and to the southeast met the Lavo Kingdom.^[4]

丹眉流國，東至占臘五十程，南至羅越水路十五程，西至西天三十五程，北至程良六十程，東北至羅斛二十五程，

...Tambralinga is 50 chéng (程) from Chenla in the east, 15 chéng from Luoyue waterway in the south, 35 chéng from Xītiān (西天) in the west, 60 chéng from Chéng Liáng in the north, 25 chéng from Luohu in the northeast...

— History of Song, volume 489^[4]

The Chinese term San-lo 三濼 mentioned in Lingwai Daida in 1178,^[5]: 288 which Lawrence P. Briggs speculated to have been an early Chinese attempt to transcribe the name of the country or the people of the upper and central Menam,^[5]: 290 was probably Chaliang.^[1]: 8 The Chinese were soon to call the region Xiān (暹) and Xiānluó (暹羅) in the 13th century.^[5]: 290 The timeframe mentioned in Chinese writings conforms to various archeological findings, which show that the region was occupied since the prehistoric period and continued until the Dvaravati period when the region was influenced by the Lavo Kingdom.^[1]: 28

To the southeast, Lavo's Lavapura faced several circumstances, such as the conquest of Lavo by Tambralinga in 927/928^{[9][10]: 23} and the 9-year-long Angkorian civil wars, which led to the destruction of Lavapura by the Angkorian king Suryavarman I in 1002.^[12] These were potentially the reasons for Lavo's decrease in influence over northern polities, which included Chaliang and Sukhothai, in the mid-10th century.

In the late 10th century, after Suphannabhum and Haripuñjaya joined forces and retook Lavapura from the Angkor in 1052 and moved the capital to Ayodhya. The seat at the former capital, Lavapura, was vacant from 1087–1106, Chaliang or Si Satchanalai's king, Kraisornrat (ไกรศรราช) then took over the seat. An attempt to re-expand influence to Lavo by the Angkor occurred in 1181 when Jayavarman VII appointed his lineage Narupatidnavarman to govern Lavapura. Due to the political pressure from the Angkor, a Tai ruler Sri Thammasokkarat (ศรีธรรมโศกราช), who was also from Si Satchanalai, fled to Nakhon Si Thammarat. However, Lavapura was probably taken back by a Tai royal from Phraek Si Racha (แพรกศรีราชา; present-day Sankhaburi) in the 13th century.

The text given in the Pu Khun Chit Khun Jot Inscription (จารึกปู่ขุนจิดขุนจอด) shows the family relationship between Nan [th] and Chaliang,^[14] which later expanded its influence on Sukhothai.^[1]: 4 This corresponds with the detail provided in the Nan Chronicles, Wat Phra That Chang Kham version.^[15]: 89

After Chaliang led by Srinaonamthum [th]^[6] annexed Sukhothai^[1]: 4 in 1157,^[6] the seat was moved to Sukhothai, which later caused the formation of the Sukhothai Kingdom in 1238.^[1]: 4 Due to the change in the direction of the Yom River, bank erosion occurred; Chaliang was moved 2.5 kilometers westward to the present-day Si Satchanalai Historical Park and was also called Sawankhalok/Si Satchanalai around the early 13th century during the reign of Si Inthrathit (Phra Ruang I; r. 1238–1270).^{[1]: 38–39} In the first era, Sukhothai kings were also considered the rulers of Chaliang until the end of the reign of Ram Khamhaeng in 1298, when Sukhothai's influence waned, allowing other vassals to gain independence;^[16] Chaliang went nearly 50 years without a ruler^[13]: 29 until Lithai was appointed to the title in 1340.^[17]: 31

According to the text given in several Sukhothai inscriptions, Chaliang or Si Satchanalai was a city-level settlement, comparable to and equal to Sukhothai, both of which were considered capital cities ruled by the kings of the Sukhothai-Si Satchanalai Kingdom.^{[1]: 25–26}

After the reign of Lithai, Sukhothai declined; both Sukhothai and Chaliang were vassals of the Ayutthaya Kingdom. According to the legend, Khottrabong (โคตรบอง) was appointed the ruler.^{[13]: 32, 35} He was dethroned probably in 1429 by an usurper, Saeng Hang (แสงหัง).^[13]: 35

During this era, Chaliang was known as Sawankalok.^[18]: 174 Historical records on Chaliang during this period are sparse.^{[1]: 9–12} After Sukhothai became the vassal of Ayutthaya, it is speculated that Chaliang together with Phitsanulok and Kamphaeng Phet were separated from the Sukhothai Kingdom by Ayutthaya under the divide and rule policy to annex and reduce the power of Sukhothai.^[19]: 10 Sukhothai and the aforementioned principalities were collectively called by Ayutthaya as the Northern cities (หัวเมืองเหนือ).^[20] Thai chronicles revised during the Rattanakosin period list these four cities as four of the sixteen vassal states of the Ayutthaya Kingdom during the reign of King Ramathibodi I. However, since the information about these vassals conflicts with other evidence, it is assumed that they were added to the chronicles later, perhaps during the reign of King Intharacha.^[7][21]

Due to the succession issue of Sukhothai which was determined by Ayutthaya, Yutthisathian [th], the son of Maha Thammaracha IV of Sukhothai, was not satisfying to be appointed as the ruler of a lower-tier city, Songkwae. He therefore pledged allegiance to Lan Na in 1452 and advised King Tilokaraj of Lan Na to invade the northern cities of Ayutthaya.^{[22]: 54–57} As a result, Ayutthaya demoted three of its four northern cities, including Songkwae, Sukhothai, and Kamphaeng Phet, from vassals to frontier cities and sent nobles to govern instead, but Chaliang remained its vassal status until it was conquered by Lan Na in 1462 and renamed Chienjuen (เชียงชื่น).^[7]