In the 14th century the centre of gravity of Thai settlement had shifted farther south from Sukhothai. In 1350 a prince of U-Thong and Lopburi founded the Kingdom of Ayutthaya, which annexed Sukhothai by the end of the 14th century and grew into a powerful state. The Thais now entered regions which had long been firmly in the hands of the Khmers: U-Thong and Lopburi were centres of Cambodian culture. In the course of numerous wars the Thais inflicted a series of defeats on the Khmers, and finally in 1431 they destroyed the Cambodian capital of Angkor.
The Thai Kings of Ayutthaya, combined the traditions of Sukhothai with the inheritance of the Khmers. Buddhism continued to be the religion of King and people, but various Hindu traditions were adopted, including the Brahman court ceremonial. Especially important was the adoption of the Hindu idea of the god-king. Whereas in Sukhothai the King was still a warrior, guardian of Buddhism and supreme judge, playing the part of a patriarchal prince, who always listened to the voice of the people, he now took on the attributes of a Hindu divinity. He became an absolute monarch with unlimited power of life and death over his subjects. The royal authority was limited only by the ethical tradition which was based on traditional Hindu prescriptions for a good ruler.
The King’s functions increased owing to his new position as a mediator between the people and the Hindu gods, himself equipped with divine powers. Numerous rites and ceremonies had to be performed by the King and a train of Brahman priests in order to assure prosperity and good fortune, the right rainfall and good crops, or to avert disasters and plagues. An example was the “first ploughing” ceremony, intended to ensure a good rice crop: this is still celebrated annually with great solemnity on the Phra Mane Ground.
The stormy initial years were followed by a period of consolidation. Administration was centralised in the capital. Provincial governors and chieftains were summoned to Ayutthaya and appointed as ministers or officials with definite, clearly determined duties. They were supported by an efficient bureaucracy. It also became the custom to assign high offices of state to princes and members of the royal family, a practice followed right down to modem times. In addition, there naturally developed at court an influential class of high officials and nobles.
The city was embellished with numerous fine buildings, and great luxury prevailed at court. The arts reached a high peak of excellence under royal patronage. It was a golden age of Thai culture, as we know from the reports of European travellers who fell under the spell of this splendid court.
Ayutthaya maintained peaceful trading relations with China. The Thais recognised the formal suzerainty of the Chinese and paid what was obviously a voluntary tribute. By so doing, they ensured that trade with their mighty neighbour, whose products, especially silk and porcelain, were much in demand, could develop unhindered.
The first Europeans to visit Thailand were the Portuguese, who concluded a trade treaty with King Rama Thibodi II in 1511. They established trading stations and missions in the capital and in Pattani. They were followed by the Dutch in 1605, the English in 1612, the Danes in 1621, and finally the French about 1662. The more arrogant the demands of the foreigners became, the more the Thais sought to play them off against each other.
During this period occurred the episode of the Greek adventurer named Constantine Phaulkon, who rose to be Prime Minister and the most powerful man in Thailand. During his rule, under King Narai, he succeeded in resisting the claims of the Dutch and the English. For this purpose he sought the support of the King of France. Embassies were exchanged between the two courts, and finally, in 1687, Louis XIV sent 500 French soldiers. French troops were established in Mergui, Bangkok and Ayutthaya, and the Thais soon realised that the French aimed at the conquest of their country. In a bloody revolt led by anti-western courtiers all the foreign soldiers were expelled, and Phaulkon was overthrown and executed (1688). After these unhappy experiences Thailand was totally sealed off from the West for more than 150 years.
The external relations of the Ayutthaya, Kingdom consisted mainly in a continuous series of major and minor wars against neighbouring states. In the 14th century the chief opponents had been the Khmers. The mid 15th century saw various unsuccessful attempts to conquer the Thai Kingdom of Chiang Mai, which maintained its independence until the 17th century, when it was overcome by the Burmese. There were also numerous campaigns against the small tributary principalities of the Malay peninsula. For Thailand’s sea-trade Pattani and Mergui were of prime importance
In the struggle for supremacy in the peninsula the main opponent of the Ayutthaya kingdom was always Burma. Burmese armies repeatedly threatened the existence of the Thai state. When, in the second half of the 16th century, the Burmese tribes had been united into a powerful Kingdom, its armies several times attacked Thailand, and in 1572 finally overran Ayutthaya. Burmese garrisons controlled Thailand under a puppet-king. But in 1587 King Naresuen (1578-94) succeeded in shaking off foreign rule and beating off farther attacks. He has since been venerated as a national hero.
Two centuries later, Burmese armies again invaded Thailand. and in 1767 Ayutthaya fell after a two years’ siege. Ayutthaya, the golden city, was pillaged, laid waste and destroyed. Irreplaceable documents, scriptures, law-books, literary works, sacred symbols and Buddha images went up in flames.