Sukhothai Kingdom

Early period

Reconstructed representations of women's traditional dress in the Sukhothai period (13th–15th centuries), based on archaeological evidence.^{[19]: 75–8}

Rulers before 1238

The following are recognised^{[by whom?]} as rulers of Sukhothai before the formal foundation of the Sukhothai Kingdom, conventionally assigned by earlier historians to 1238. Some dates derive from chronicle traditions and should be treated as approximate. The order of the entries from Sri Naw Nam Thum to 1238 is not agreed. The arrangement below follows a reading in which Pha Mueang held Sukhothai before his father. Phiset Jiajanphong instead reads the Wat Si Chum Inscription as making Sukhothai his father's seat, which passed to Khom Sabat Khlon Lamphong on his death.^[34]: 11

More information Ruler, Reign ...

Ruler		Reign
Romanised name	Thai name
Dvaravati network under the Lavo Kingdom
Indrajayadhirāja[21]: 3–4	อินทราไชยธิราช	679–687
Balidhiraja[b][21]: 3–4	พาลีธิราช	687 – mid-8th century
Under Indaprasthanagara / Qiān Zhī Fú
Unknown		757–?
Name unknown[c]		c. 867
Abandoned?[35]: 8		Late 8th century – 957
Under the Haripuñjaya Kingdom
Abhayakamini[32]	อภัยคามินี	957[35]: 9–10 –959?
Sricandradhipati[32] (Phra Ruang II)	ศรีจันทราธิบดี	959–?
As the free city-state of Si Satchanalai–Sukhodaya
Arunaraja (Phra Ruang I)	อรุณกุมาร	?–1052[35]: 18
Ruled from Mueang Chaliang		Late 11th – early 12th century
The polity split in two: Si Satchanalai and Kamphaeng Phet–Sukhodaya
Under Indaprasthanagara
Śayarāṅgarāja[36]: 80	ไสยรังคราช	1138–?
Pra Poa Noome Thele Seri	พนมทะเลศรี	1155?–1156/57
Suryaraja[d]	สุริยราชา	1156–1184
De facto independent by c. 1204
Candraraja[37]: 11	จันทราชา	1184–1214[37]: 17
E Daeng Phloeng	อีแดงเพลิง	1214?–1219
The two seats were merged
Pha Mueang[e]	ผาเมือง	Ceded the throne to Sri Naw Nam Thum
Sri Naw Nam Thum[f]	พ่อขุนศรีนาวนำถุม	1219–?
Khom Sabat Khlon Lamphong	ขอมสบาดโขลญลำพง	?–1238
Pha Mueang[e]	ผาเมือง	1238
1238: traditional formation of the Sukhothai Kingdom

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Notes

1. [a]

   See Pra Poat honne Sourittep pennaratui sonanne bopitra § Dynastic traditions for the calculation.
2. [b]

   Son of Kalavarnadisharaja, king of Lavo.
3. [c]

   Adoptive father of Balaraj of Dvaravati Nakhon Pathom.
4. [d]

   Seat at Vicitraprakāra, modern Kamphaeng Phet.
5. [e]

   A reading of the Wat Si Chum Inscription suggests that Pha Mueang took Sukhothai twice before finally ceding it to Si Inthrathit in 1238.^[38]
6. [f]

   Tai monarch from Mueang Chaliang.

Kingdom establishment

Organisation of rule before Ram Khamhaeng

Phiset Jiajanphong reads the Wat Si Chum Inscription as placing Sukhothai, Si Satchanalai, and Sralwang Songkhwae (modern Phitsanulok) under the rule of Pha Mueang's line. This arrangement, he argues, existed during the reign of Pha Mueang's father, Sri Naw Nam Thum, before Sukhothai passed to Khom Sabat Khlon Lamphong following his father's death.^{[34]: 11, 13} Chusak Satienpattanodom interprets the period after 1238 as one of rule from two centres. In his account, Sukhothai passed to Si Inthrathit's line, while Si Satchanalai remained under Pha Mueang's line, along with Mueang Rat and Song Khwae, which were held by Phaya Khamhaeng Phra Ram [th]. Chusak identifies Khamhaeng Phra Ram as Pha Mueang's younger brother, interpreting the genealogies in the Wat Si Chum and Wat Phra Yuen inscriptions, whereas Phiset leaves open whether the relationship was that of brother or son.^[67]: 81

Inscriptions of the period name the two cities together. Chusak interprets this paired designation as a claim to rank above the other town rulers rather than as a territorial title. On the same reading, Si Satchanalai was the seat from which an heir ruled before succeeding to Sukhothai.^{[67]: 74–78} Phiset draws an inference about rank from Pha Mueang's conduct in 1238. Pha Mueang entered Sukhothai first, consecrated Bang Klang Hao there, and then returned to Mueang Rat. Phiset interprets this sequence as indicating that Mueang Rat ranked no lower than Sukhothai.^[34]: 16

On Phiset's reading, this arrangement gradually came to an end. Sralwang Songkhwae may have passed to Si Inthrathit's line as early as the reign of Ram Khamhaeng, perhaps with the consent of Pha Mueang's family, since the inscription speaks favourably of Ram Khamhaeng.^[34]: 13 Phiset suggests that the transfer was based on conditions attached to the person of the ruler at Sukhothai. He notes that Sri Sattha was educated as a boy in the subjects of a man preparing to rule a city, but took monastic vows after the political circumstances of his time had changed.^{[34]: 13, 15} Chusak dates the return of Si Satchanalai to the Sukhothai ruler to 1283, after Pha Mueang's death, when Ram Khamhaeng annexed it. This date derives from the preface to the Chindamani [th], a seventeenth-century manual, rather than from an inscription.^[67]: 82

The inscriptions do not state when or why Pha Mueang's family left, and Phiset argues that the question depends on first identifying Mueang Rat.^[34]: 15 He also cites the Northern Chronicle, which describes Hariphunchai, Thung Yang, Sawankhalok, and Boribun as towns ruled by their own kings, with none involved in the affairs of the others.^[34]: 47 The chronicle, however, was compiled only in the early Bangkok period, several centuries after the events it describes.^[67]: 26

Expansion under Ram Khamhaeng

Si Inthrathit died in 1270 and was succeeded by his son Ban Mueang, and Ban Mueang in turn by his brother Ram Khamhaeng the Great. Both carried Sukhothai beyond the borders their father had set. To the south, Ram Khamhaeng subjugated the mandala kingdoms of Suvarnabhumi (likely present-day Suphan Buri) and Tambralinga (present-day Nakhon Si Thammarat). Through Tambralinga he is said to have adopted Theravada Buddhism as the state religion, a claim of the traditional historians that is disputed.^[4]: 3–4

To the north, Ram Khamhaeng placed Phrae and Muang Sua (present-day Luang Prabang, Laos), among other mandala city-states, under tribute. To the west he supported the Mon people under Wareru, said to have eloped with his daughter, in their revolt against Pagan. Wareru went on to found a kingdom at Martaban, the predecessor of Hanthawaddy at present-day Bago. Martaban is traditionally counted a Sukhothai tributary, though Sukhothai's reach may not have extended so far.^[4]: 4 By gathering vassals in this way he could claim suzerainty from Luang Prabang to Nakhon Si Thammarat and from Vientiane to Pegu. The southern end of that claim rests on a passage of contested date. Baker and Pasuk read the naming of Ligor as a dependency, on the fourth face of the inscription and in the corresponding clause of the Ayutthaya Palace Law, as a later insertion in both texts.^[69]: 50 His success rested largely on his reputation in the field, and the bonds of vassalage he had built fell apart soon after his death in 1298, his successors commanding no comparable authority.^[70] Phiset Jiajanphong makes the same point about the evidence. He argues that Ram Khamhaeng's standing as a warrior king led to readings of Sukhothai's administrative extent far wider than the conditions of the time allow. On his account the first inscription records a network of relationships with the surrounding polities, reaching south to Suphannaphum and Nakhon Si Thammarat, rather than rule over them.^[29] Sujit had argued in 1983 that the list records an aspiration resting on claims of kinship, since Lan Xang, Lavo–Ayodhya, Suphannaphum and Nan kept rulers of their own.^{[71]: 87–88} He put its northern limit at the Nan River and its southern at Nakhon Sawan. To the east it reached Nakhon Thai and the Pa Sak valley, and to the west the Ping between Tak and Kamphaeng Phet.^{[71]: 87–88}

A Lankan-trained monk later reordained 7,520 monks at Sukhothai, after which the king had his ministers and a thousand citizens ordained into the new order.^[60]: 38 The most fully recorded of these conversions is that of Si Sattha [th], a grandson of Pha Mueang. By his own inscription he saw that the world of rebirths was impermanent, destroyed his weapons, renounced his princely caste and left his home for the forest. He took the name Si Sattha, travelled the region founding and restoring religious sites, and on one occasion went through a market buying up every living creature and setting it free.^[60]: 38

In religion and culture, Ram Khamhaeng brought monks from Sri Thamnakorn to propagate Theravada Buddhism. The Sukhothai script was probably his work, in 1283; its earliest witness is the Ram Khamhaeng Inscription, found by Mongkut nearly six centuries later. From it the modern Thai script developed.

Relations with Yuan China began in the same reign, and Sukhothai started sending trade missions.

Decline and tributary status

By the early 14th century Sukhothai held the Chao Phraya plain, with spurs west to the Hanthawaddy kingdom and south to the Nakhon Si Thammarat Kingdom. A Chinese notice of the same years gives a different picture. The Guangzhou gazetteer of 1297–1307 has Xiān controlling Shang-shui Sù gū dǐ, Sù gū dǐ being Sukhothai; Baker and Pasuk leave Shang-shui open, as either a further place name or a statement that Sukhothai lay upriver from Xiān.^{[69]: 45–46} Ram Khamhaeng was succeeded by his son Loe Thai.

The tributaries fell away quickly after his death. The dominions north of Uttaradit, among them the Lao kingdoms of Muang Sua and Vieng Chan Vieng Kham, present-day Vientiane, broke free. In 1319, Martaban in the west broke away. After 1321, Lan Na (the successor state to Ngoenyang) gained influence over Tak, one of the oldest towns in Sukhothai. To the south, Suphannaphum Kingdom and Nakhon Si Thammarat left early in Loe Thai's reign, cutting Sukhothai off from its vassals beyond them. The kingdom was soon back to what it had been, a small local power.^[72]

Baker and Pasuk describe the same decades as a reorganisation of the region rather than a simple contraction. Between the end of the 13th century and the middle of the 14th, three loose confederations took shape. Lan Na emerged in the far north with its capital at Chiang Mai, legendarily founded in 1296. Lan Xang formed around the middle Mekong in the mid-14th century. The third, along the fringe of the hills, acquired no name of its own and was known from Ayutthaya as the Northern Cities.^[60]: 34 Sukhothai belonged to the third, where its house was first among equals rather than sovereign. Under Ram Khamhaeng's successor the territory fragmented, nine or ten local chiefs going their own way.^[60]: 36

In 1323, Loe Thai was succeeded by his cousin, Ngua Nam Thum. In 1347, he was succeeded by Li Thai (Maha Thammaracha I), the son of Loe Thai. In 1349 armies from Ayutthaya invaded and made Sukhothai a tributary.^[5]: 222 The centre of power shifted to Song Khwae, present-day Phitsanulok, and in 1378 Lue Thai submitted as a vassal.^{[73]: 29–30} He was succeeded by Sai Lue Thai (Maha Thammaracha III) in 1399.

Baker and Pasuk read those years differently at two points. Li Thai took Sukhothai by force, attacking the city and breaking its gates, and the title Phra Maha Thammaracha that he adopted then spread beyond him. Branches of his clan broke away to rule other cities; at times more than one town ruler held the title at once, and other clans developed titles of their own, particularly at Phichai and Kamphaeng Phet. They ascribe the move of the political centre to Phitsanulok not to the subjection of 1349 but to strategic or commercial advantage, or to a hinterland too poor to support a large population. They also note that Sukhothai's prominence as a political centre lasted less than a century.^[60]: 36

A law stone found at Wat Sa Si in Sukhothai, Inscription 38, bears on the city's standing in these years. Prasert na Nagara read its ruler as Ramaracha, enthroned in 1395, and dated the law to 1397. M.C. Chand Chirayu Rajani objected that the figure is not legible and the date computed, and preferred the later Ayutthayan king Nakharinthrathirat. Phiset accepted the date of 1397 but gave the stone to Nakharinthrathirat while he governed Kamphaeng Phet apart from the Ayutthayan court, on the ground of his kinship with the rulers of Sukhothai. Nakharinthrathirat took the Ayutthayan throne in 1409. All three hold that the stone, though found at Sukhothai, was not made by Sukhothai people.^{[34]: 25–26}

In 1424, after the death of Sai Lue Thai, his sons Phaya Ram and Phaya Ban Mueang fought for the throne. Intharacha of Ayutthaya intervened and installed Ban Mueang as Borommapan (Maha Thammaracha IV). When Borommapan died in 1438, Borommarachathirat II of Ayutthaya installed his son Ramesuan (the future Borommatrailokkanat of Ayutthaya) as Upparat in Sukhothai. The position resembled both that of a viceroy and that of an heir presumptive. The appointment established a form of personal union and created the Siamese Front Palace system. Ramesuan presumably brought Ayutthayan officials and a garrison with him, which ended Sukhothai's independence.^[74]

Annexation and further influence

Under tributary status, the former territories of Sukhothai, known to the people of Ayutthaya as the Northern Cities (Thai: เมืองเหนือ, RTGS: Mueang Nua), continued under local aristocrats within Ayutthaya's overlordship, on the mandala pattern common to both. The two merged politically and culturally over the 15th and 16th centuries, and Sukhothai warfare, administration, architecture, religion and language all left marks on Ayutthaya. Sukhothai nobles linked themselves with the Ayutthayan elite through marriage alliances, and often played the role of kingmaker in Ayutthayan succession conflicts. Sukhothai commanders served prominently in the Ayutthayan army, its military tradition being reckoned the tougher.^[75]

How that process should be described is contested. Baker and Pasuk reject the older account of conquest or absorption, holding that it applies a model of sovereignty foreign to a region where a defeated ruler remained a king and an overlord imposed no administration. They note that Borommaracha I's five expeditions of the 1370s fall on the same places again and again, and that the chronicle verb ao means to take or attack rather than to hold.^[69]: 60 They also reject reading the tears of blood reported of the Phra Jinaraja image in 1438 as a figure for Sukhothai's subjection, since the chronicles use no such metaphor elsewhere.^{[69]: 59–60, 63} In its place they set the marriages, following Phiset Jiajanphong. Borommaracha I, Intharacha and Borommarachathirat II each took a daughter of Li Thai as consort, and the exchange ran both ways, a senior queen at Sukhothai bore an Ayutthaya title and donated an Ayutthaya-style Buddha image.^[69]: 61 Queens travelled with entourages of nobles, monks and craftsmen, while northern nobles went south to serve a wealthy merchant city that needed soldiers.^[69]: 62

From 1456 to 1474, former Sukhothai territory became a battleground during the Ayutthaya-Lan Na War (1441–1474). In 1462, Sukhothai briefly rebelled against Ayutthaya and allied itself with their enemy, Lan Na. In 1463 Borommatrailokkanat moved the royal residence to Song Khwae, presumably to be nearer the front. He walled it together with its twin town of Chainat and probably gave the joined towns the name Phitsanulok.^[69]: 64 How long he stayed is disputed. The chronicles keep him there until his death in 1488, the Sangitiyavamsa has him abdicate after twenty years, and Chinese records report an abdication in 1482/3 on grounds of age.^[69]: 64 Contemporary Portuguese traders described Ayutthaya and Phitsanulok as "twin states".^[75]

The Northern Cities remained royal through this period. Their traditional titles were still in use in the 15th and early 16th centuries. They were Maha Thammaracha at Phitsanulok, Phaya Chaliang at Chaliang and Sawankhalok, Phaya Ramaraj at Sukhothai, and Phaya Saen Soi Thao or Dhammasokaraja at Kamphaeng Phet. Tomé Pires wrote of the ruler of Kamphaeng Phet that within his own territory he was like the king of the land. An inscription of 1510 shows him restoring the relic stupa, casting a Shiva image, dredging a river, setting boundary markers and repairing irrigation channels.^{[69]: 67–68} The cities were flourishing rather than reduced. Chaliang–Satchanalai and Kamphaeng Phet were refortified and given new temple complexes in the manner of a royal capital, and the walls of Sukhothai gained two further rings. Piriya Krairiksh has argued partly on that ground that many buildings conventionally dated to the 13th and 14th centuries were built or much extended later.^[69]: 68 Kessara Srinaka reports that Piriya reached those datings from contemporary foreign maps, drawings and travel accounts, and that some of the works he redated were moved two to three centuries from the conventional attributions.^[76]: 24 Writing in the 1550s from the reports of traders and mercenaries, João de Barros presented the core territory as two kingdoms. The northern was Chaumua, which he glossed as the northern people and in which he named Sukhothai and Sawankhalok. Below it lay Muantay, which he said was more properly called Sião. He added that the two spoke different languages, and some Portuguese maps of the period show Odia and Sian as separate places.^[69]: 69

In 1548, Maha Chakkraphat named Khun Phirenthorathep, a noble of royal Phra Ruang descent, as the ruler of Phitsanulok. He was given the name Maha Thammaracha, after the historical kings of Sukhothai, and married a daughter of Maha Chakkraphat, which strengthened his claim on both the old line and the new. Despite this, the title of Upparat went to Maha Chakkraphat's son Ramesuan (who died in 1564) and later his brother Mahinthrathirat. After a series of wars with the Burmese Toungoo Empire he took the Burmese side against Ayutthaya. In 1569, Ayutthaya under Mahinthrathirat fell to the Burmese, and Bayinnaung installed Maha Thammaracha (Sanphet I) as the vassal king in Ayutthaya and the first king of the Sukhothai dynasty.^[75]

In 1584, Maha Thammaracha and his son, the Upparat and future Naresuan the Great (Sanphet II), would free Ayutthaya from Burmese overlordship in the Burmese-Siamese War of 1584–1593. After the Battle of the Sittaung River, Naresuan forcibly relocated people from the northern cities of Phitsanulok, Sukhothai, Phichai, Sawankhalok, Kamphaeng Phet, Phichit, and Phra Bang closer to Ayutthaya.^[77][78] Since then, the ruins of the capital city of the former Sukhothai Kingdom have been preserved as the Sukhothai Historical Park and designated a World Heritage Site.^[79]

Readings of 1238

Interpretations of the events of 1238 have changed over time. Briggs presented the episode in this form in 1950.^[31]: 300 In the older account, the holder of the Khmer-style title was described as the commander of a Khmer garrison, implying a prior military occupation. The episode consequently became the liberation of Sukhothai from Khmer suzerainty and the establishment of an independent kingdom under a Tai dynasty.^[60]: 35 In 1981, Srisakra Vallibhotama argued that the Wat Si Chum Inscription showed no more than a contest among towns in the Sukhothai area, and that their ties to Cambodia involved alliances and marriage.^{[71]: 15–16} Sujit Wongthes identified Khom Sabat Khlon Lamphong as a ruler from a related polity of the Kamboja group centred on Lavo.^[71]: 131 Baker and Pasuk argue that both the ethnic framing and the idea of liberation were imported from a later era. They instead interpret the inscription as recording a victory by one local lord associated with Angkor over another warrior who held a Khmer title.^[60]: 35 Walailak Songsiri interprets the title in similar terms. Chinese records apply kamrateng to the rulers of Sukhothai, Phrip Phri, and Chen Li Fu alike. She argues that the title, together with the accompanying Indic royal names, was adopted from the Khorat Plateau and the Tonlé Sap for formal address at the Chinese court, rather than as an indication of subordination. The more than sixty settlements dependent on Chen Li Fu had rulers of their own who did not bear the title.^[48]: 8 In 2001, Wyatt set aside the ethnic framing, arguing that the division between the two sides was religious and cultural rather than ethnic. He also stated that he could find no adequate explanation for the timing, given his premise that Angkor controlled the region. The grievances he identified in the Ram Khamhaeng inscription would have persisted over a long period. A weakening of Angkor should, on that premise, have produced comparable risings at other times, such as after the Cham sack of Angkor in 1177, which did not occur.^{[50]: 54, 62}

The epigraphic evidence bears on all these interpretations. For the reign of Jayavarman VII, 1181–1218, Baker and Pasuk report that the Chao Phraya plain has yielded none of the temple-endowment inscriptions characteristic of Angkorian provinces. They add that his hospital and fire-house foundations, numbering 107 and 121 respectively, extend no farther west than Prachin Buri. They interpret the spread of Angkorian styles across the plain as evidence of cultural influence rather than administration.^{[60]: 22–4} Wyatt reaches a similar conclusion from a different body of evidence. Of the sixteen dated inscriptions from 1168 to 1219 that he surveys, those from Grahi and Lopburi show no indication of Angkorian political or administrative power. Those from Prachin Buri and the Khorat Plateau provide evidence of its presence, including seven hospital inscriptions on the plateau dated to 1186. He adds, however, that the absence of such references is not conclusive.^{[50]: 50–51}

The affiliations of the winning side also bear on this interpretation. Pha Mueang received a Khmer title, a regalia sword, and a princess in marriage from the ruler at Angkor. Bang Klang Hao later adopted the regnal name Si Inthrathit, the same title conferred on Pha Mueang, when Pha Mueang declined the two towns and instead invested him. Baker and Pasuk compare this sequence with the founding of Lan Xang, in which a local chief travelled to Indaprasthanagara, returned with a princess from its ruling court as his wife, and subdued the surrounding chiefs. They argue that in both cases local rulers derived legitimacy from association with a dominant polity rather than from separation from it.^[60]: 35 Under the name Si Inthrathit, Bang Klang Hao is traditionally said to have secured Sukhothai and founded the Phra Ruang dynasty, whose influence subsequently extended over neighbouring settlements in the upper Chao Phraya valley.

Abandonment of the first-capital doctrine

The doctrine that Sukhothai was the first royal capital of the Thai has a documented origin. Vajiravudh set it out in the souvenir volume of the Siamese Kingdom Exhibition held at Lumphini in 1925. In his words, between 1247 and 1350, when Sukhothai was the royal capital, the Thai nation had newly established itself as a consolidated whole, independent and subject to no one.^[80]: 145 Saipan Puriwanchana identifies two currents behind this formulation. One was the nationalism that entered elite Siamese historical thinking between the reigns of Mongkut and Chulalongkorn. The other was the Romanticism that influenced Vajiravudh during his years of study in England from 1893 to 1901 and emphasized a great collective past.^[80]: 150 She adds that this picture rests on Inscription 1, the only Sukhothai inscription widely known in Thailand through school textbooks.^[80]: 147 Sujit Wongthes argues that the phrase was established a century ago by Thai elites along nationalist and racial lines.^[29] He had argued in 1983 that the doctrine excluded Lan Na, the northeast, and Nakhon Si Thammarat from Thai history.^{[71]: 68–71}

Saipan presents the archaeological position, drawing on Srisakra Vallibhotama, as contradicting the doctrine. In this interpretation, Sukhothai was one polity among the ancient states of the Thai lands, a trading town on the Yom valued for its forest products and its position at the intersection of routes between city-states.^[80]: 146 Sujit Wongthes reports that the Fine Arts Department has since abandoned the phrase. Its 2015 publication, History of the Thai Nation (ประวัติศาสตร์ชาติไทย), previously described Sukhothai as the first kingdom regarded as a kingdom of the Thai. However, the later publication, Thai City-States on the Land of Suwannaphum (นครรัฐไทยบนแผ่นดินสุวรรณภูมิ), published in 2019, refers to Sukhothai simply as a state instead.^[29]

Ceramic industry

Sukhothai’s best-known export was sangkhalok ware; this was the only period in which Siam made Chinese-style ceramics, and they are usually said to have fallen out of use by the 14th century. Baker and Pasuk give the industry a much longer life, with celadon from the Sukhothai kilns to the 1480s and a darker Sawankhalok ware from Chaliang–Satchanalai until the 1580s. The export trade ended only when Ming China lifted its ban on ceramic exports in 1567.^{[69]: 68–69}

Excavation has since given the industry absolute dates. At Tao Thuriang, the kiln field beside the moat of Wat Phra Phai Luang, 61 kilns have been recorded, 11 of cross-draft and 50 of up-draft type; three radiocarbon determinations on charcoal calibrate to 1340–1400, 1350–1390 and 1424–1460. Thongchai Sako reads these as two periods of building, the first from about 1340 to 1400 and the second from the early 15th century to about 1530.^{[81]: 173–183} At Si Satchanalai 186 kilns have been recorded on the Yom, 182 on the west bank and four on the east. One kiln type, cut into the ground and lined with slabs, is found there but not at Sukhothai. From ten thermoluminescence dates taken in 2012, Bundit Thongaram places the kiln 61 complex at about 1478–1555. He rejects the five radiocarbon dates obtained in 1986 as too broadly spread to be relied on, and reports without adopting an 11th-century date proposed for kiln 101 by Don Hein in 1980.^{[82]: 197–201} Architectural ornament from the same kilns is found in monasteries of the Sukhothai and Ayutthaya kingdoms but not abroad. The export wares reached wrecks in the Gulf of Thailand and sites in Java, Sumatra, the Philippines, Sri Lanka and the Ryukyus.^{[82]: 203–205} Suthipob Chantrapakajee states that the sale of the ware was a royal monopoly of Ayutthaya between 1438 and 1530.^[83]: 143

Metal production

The Sixth Regional Office of the Fine Arts Department has surveyed the headwaters of the Mae Lamphan (แม่ลำพัน), a tributary of the Yom about 20 km north-west of the old city. It has recorded ancient mines there and more than a hundred iron-smelting furnaces.^{[84]: 13–14} Ore was gathered at the surface and cut from pits more than 10 m deep along haematite and magnetite veins. The furnaces were cylindrical, 1.0 to 1.5 m across, with paired oval channels at the base for air, and worked by the direct bloomery process.^{[84]: 14–15} Excavation beside the Kong Khai stream in 2018 opened a slag dump and a second pit holding at least six furnaces. Thermoluminescence on furnace walls and radiocarbon on charcoal in slag place production between 1128 and 1280.^[84]: 19

Machetes, chisels and iron nails have also been excavated inside the walled city, which Theerasak Thanusilp reads as supply from the hills to the town.^[84]: 16 Bronze slag, crucibles with bronze residue and cast ornaments were found on the same ground. He proposes that Sukhothai bronze casting drew on metallurgical knowledge accumulated in these communities since the prehistoric period. He notes that no finished object has yet been found at a production site, and that the compositional and lead-isotope analysis needed to test the proposal has not been made.^{[84]: 16–17, 19}