The period was described as a "golden age" of Siamese culture and saw the rise in Chinese trade and the introduction of capitalism into Siam,[24] a development that would continue to expand in the centuries following the fall of Ayutthaya.

[64] However, since he had no male heir, he had his only daughter marry Sai Nam Peung (สายน้ำผึ้ง),[65] son of Kraisornrat (ไกรศรราช) who was of Mon's Chaliang and Tai's Chiang Saen lineages and served as the Lavapura king at that time.

During the pre-Aytthaya period, Ayodhya was mentioned as Xiān (暹; or Siam) in several Chinese and Đại Việt texts from 1149[40]:line 61 to the official establishment of the Ayutthaya Kingdom in 1351.

[70]: 70  According to The Customs of Cambodia written by Zhou Daguan as an official delegation sent by the Yuan Dynasty to Angkor from 1296–1297, the Siamese people exerted significant influence over Lavo's Lavapura and appeared in huge numbers in the Angkorian capital of Yasodharapura.

[23] In 1605, Naresuan died of illness while on campaign against a Burmese spillover conflict in the Shan region, leaving a greatly expanded Siamese kingdom to be ruled by his younger brother, Ekathotsarot (Sanphet III).

[90]: 173–180  Ekathotsarot's reign was marked with stability for Siam and its sphere of influence, as well as increased foreign interactions, especially with the Dutch Republic, Portuguese Empire, and Tokugawa Shogunate (by way of the Red Seal Ships), among others.

Indeed, representatives from many foreign lands began to fill Siam's civil and military administration – Japanese traders and mercenaries led by Yamada Nagamasa, for example, had considerable influence with the king.

Nonetheless, Si Saowaphak succeeded to the throne against his late father's wishes, and led a short and ineffective reign in which he was kidnapped and held hostage by Japanese merchants, and later murdered.

[91] While a community of Japanese exiles were eventually welcomed back into the country, this event marks the end of the Tokugawa Shogunate's long-standing formal relationship with the Ayutthaya Kingdom.

[90]: 216–217  Narai finally assumed a stable position as King of Ayutthaya with the support of a mainly foreign court faction consisting of groups that had been marginalized during the reign of his father, Prasat Thong.

[91]: 63  This hostile attitude was especially directed at Constantine Phaulkon, a Catholic Greek adventurer and proponent of French influence who had climbed to the rank of Narai's Prime Minister and chief advisor of foreign affairs.

[98] While members of the anti-foreign court faction were primarily concerned with Catholic influence, there is evidence to suggest that Narai was equally interested in Islam, and had no desire to fully convert to either religion.

However, Ayutthaya kings only occasionally viewed themselves as the defender of "the kingdom, people [sic], and Buddhism", which wouldn't be fully realized until the Thonburi and Bangkok regimes in response to the traumatic destruction of the Siamese state in 1767.

It however lacked the men to arm these weapons, with the failure of the Ayutthaya corvee system and increased economic incentives for phrai to escape due to greater integration with the world's economy over the past 150 years of peace.

[108][109]: 116  Aung Zeiya, a local Burmese leader, arose against the Mons and reconquered Upper Burma, proclaiming himself King Alaungpaya and establishing militaristic regime of the new Konbaung dynasty.

Phraya Tak, a Siamese military man of Chinese heritage, upon realizing hopelessness in defenses of Ayutthaya, gathered men and broke through Burmese siege in January 1767 to seek for new position in Eastern Siam.

[125][126] He gathered his forces and retook the ruined capital of Ayutthaya from the Burmese garrison at Pho Sam Thon in June 1767, using his connections to the Chinese community to lend him significant resources and political support.

[129] The city, described by a Danish visitor in 1779 to be a "terrible spectacle", totally buried in undergrowth and inhabited by elephants and tigers,"[129] was resettled quite soon after, with former Ayutthaya temples being used for festivals and celebrations following the sack.

[136] While there is no concrete evidence that this land management system constituted a formal palace economy, the French François-Timoléon de Choisy, who came to Ayutthaya in 1685, wrote, "the king has absolute power.

[137] In addition to the sakdina system, another of the numerous institutional innovations of Borommatrailokkanat was to adopt the position of uparaja, translated as 'viceroy' or 'prince', usually held by the king's senior son or full brother, in an attempt to regularise the succession to the throne – a particularly difficult feat for a polygamous dynasty.

'[139] Although European visitors to Thailand at the time tried to discern any rules in the Siamese order of succession, noting that in practice the dead king's younger brother often succeeded him, this custom appears not to have been enshrined anywhere.

According to a French source, Ayutthaya in the 18th century included these principal cities: Martaban, Ligor or Nakhon Sri Thammarat, Tenasserim, Junk Ceylon or Phuket Island, Singora or Songkhla.

Terwiel, this process occurred with an accelerated pace during the reign of King Borommatrailokkanat (1448–1488) who reformed Siam's model of governance by turning the Siamese polity into an empire under the mandala feudal system.

It allowed Siamese poets to compose in different poetical styles and mood, from playful and humorous rimed verses, to romantic and elegant klong and to polished and imperious chan prosodies modified from classical Sanskrit meters.

Thailand's national epic is a version of the story of Rama-Pandita, as recounted by Gotama Buddha in the Dasharatha Jataka called the Ramakien,[158] translated from Pali and rearranged into Siamese verses.

[159] By the late period of the Ayutthaya Kingdom, it had attained the current shape as a long work of epic poem with the length of about 20,000 lines, spanning 43 samut thai books.

In the highlands, where rainfall had to be supplemented by a system of irrigation[172] to control water levels in flooded paddies, the Thais sowed the glutinous rice that is still the staple in the geographical regions of the north and northeast.

When word spread that Narai was dying, a general, Phetracha (reigned 1688–1693) staged a coup d'état, the 1688 Siamese revolution, seized the throne, killed the designated heir, a Christian, and had Phaulkon put to death along with a number of missionaries.

From Ayutthaya, Japan was interested in purchasing Chinese silks, as well as deerskins and ray or shark skins (used to make a sort of shagreen for Japanese sword handles and scabbards).

[3][182] The nationalist-themed histories of Ayutthaya, pioneered by Prince Damrong, primarily featured the stories of kings fighting wars and the idea of territorial subjugation of neighboring states.