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Kings

In its early maritime phase, Ayutthaya rulers were leaders of a port city. Ma Huan described the ruler of Ayutthaya in the 15th century as a ruler wearing gold-trimmed pants who rides on an elephant inspecting the city with one attendant and a ruler who lives in a modest-looking residence. Their relationships to the other cities were a first among equals status. Early Ayutthaya rulers had to balance their interests alongside those of their city vassal states. As Ayutthaya incorporated the Northern Cities and adapted their government functions in the 15th and 16th centuries, Ayutthaya rulers became more regal and assumed more power at the cost of their vassal cities. As the kings became richer through trade in the 17th century, they used their wealth to express their power, including the shrouding of the monarch in Angkorian and Brahmic rituals and symbolism.

The kings of Ayutthaya from the 17th century onwards were absolute monarchs with semi-religious status. Their authority derived from the ideologies of Hinduism and Buddhism as well as from natural leadership. The king of Sukhothai was the inspiration of Inscription 1 found in Sukhothai, which stated that King Ramkhamhaeng would hear the petition of any subject who rang the bell at the palace gate. The king was thus considered as a father by his people.

At Ayutthaya, however, the paternal aspects of kingship disappeared. The king was considered the chakkraphat (Sanskrit chakravartin) who through his adherence to the law made all the world revolve around him. According to Hindu tradition, the king is the avatar of Vishnu, destroyer of demons, who was born to be the defender of the people. The Buddhist belief in the king is as righteous ruler (Sanskrit: dharmaraja) who strictly follows the teaching of Gautama Buddha and aims at the well-being of his people.

The kings' official names were reflections of those religions: Hinduism and Buddhism. They were considered as the incarnation of various Hindu gods: Indra, Shiva, or Vishnu (Rama). The coronation ceremony was directed by brahmins as the Hindu god Shiva was "lord of the universe". However, according to the codes, the king had the ultimate duty as protector of the people and the annihilator of evil.

According to Buddhism, the king was also believed to be a bodhisattva. One of the most important duties of the king was to build a temple or a Buddha statue as a symbol of prosperity and peace.

For locals, another aspect of the kingship was also the analogy of "The Lord of the Land" or "He who Rules the Earth" (Phra Chao Phaendin). According to the court etiquette, a special language, Rachasap (Sanskrit: Rājāśabda, 'royal language'), was used to communicate with or about royalty. In Ayutthaya, the king was said to grant control over land to his subjects, from nobles to commoners, according to the sakna or sakdina system codified by King Borommatrailokkanat (1448–1488). The sakdina system was similar to, but not the same as feudalism, under which the monarch does not own the land. 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. He is truly the god of the Siamese: no-one dares to utter his name." Another 17th century writer, the Dutchman Jan van Vliet, remarked that the King of Siam was "honoured and worshipped by his subjects second to god." Laws and orders were issued by the king. For sometimes the king himself was also the highest judge who judged and punished important criminals such as traitors or rebels.

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. In practice, there was inherent conflict between king and uparaja and frequent disputed successions. However, it is evident that the power of the throne of Ayutthaya had its limits. The hegemony of the Ayutthaya king was always based on his charisma based on his age and supporters. Without supporters, bloody coups took place from time to time. The most powerful figures of the capital were always generals, or the Minister of Military Department, Kalahom. During the last century of Ayutthaya, bloody fighting among princes and generals, aiming at the throne, plagued the court.

With the exception of Naresuan 's succession by Ekathotsarot in 1605, 'the method of royal succession at Ayutthaya throughout the seventeenth century was battle.' 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. The ruling king did often bestow the title of uparaja upon his preferred successor, but in reality, it was an 'elimination process': any male member of the royal clan (usually the late king's brothers and sons) could claim the throne of Ayutthaya for himself, and win by defeating all his rivals. Moreover, groupings of nobles, foreign merchants, and foreign mercenaries actively rallied behind their preferred candidates in hopes of benefiting from each war's outcome.