His preference of being a monk rather than keeping the throne earned him the epithet "Khun Luang Ha Wat"[3] (Thai: ขุนหลวงหาวัด), or "the king who lives in the temple".

[5]: 298–300 His memorial tomb is located in the Lin Zin Gon (Kone) cemetery in Amarapura, about 500m north east of the U Bein Bridge.

Shortly before Uthumphon's birth, his father Prince Phon dreamed of seeing flowers of Udumbhara or Buddhist holy fig.

Uthumphon was the youngest child[8] born to his mother Princess Consort Phlap, being more than ten years younger than his older brother Ekkathat.

Prince Thammathibet, eldest son of Borommakot and Uthumphon's half-older brother, was appointed as Uparat[7] or Wangna or vice king of the Front Palace in 1741, technically as heir presumptive.

After the death of Chaophraya Chamnan Borirak the Chief Minister in 1753, the Siamese royal court was plunged into princely conflicts.

Uthumphon underwent Uparajabhisekha ceremony to be consecrated as the new Uparat or Prince of the Front Palace and technically heir presumptive to his father Borommakot in 1757.

Uthumphon asked five senior Buddhist prelates, led by Phra Thepmuni the abbot of Wat Kudidao temple,[11] to persuade the Three Princes to surrender peacefully.

A week later, on he eleventh waning of the sixth month[9] (2 May 1758), the Three Princes visited Uthumphon and Ekkathat at Suan Kratai Pavilion to supposedly surrender.

The new king Uthumphon, after subjugating his rivals the Three Princes, was finally enthroned in the Praptabhisekha ceremony on the sixth waxing of the seventh month[9] (12 May 1758).

Praptabhisekha was a specific name of a Rajabhisekha royal enthronement ceremony for a Siamese monarch who had to defeat enemies before ascension to the throne.

Ekkathat moved to stay at Suriyat Amarin Throne Hall, a splendid royal pavilion, instead of returning to Wat Lamut temple as Buddhist monk to impose political pressure onto Uthumphon.

Uthumphon went on a royal barge procession to Wat Ayothaya temple in the northeastern outskirts of Ayutthaya to perform an ordination ceremony to become a Buddhist monk.

Uthumphon's abdication and entrance into the Theravadin Buddhist religion earned him the epithet Khun Luang Ha Wat (Thai: ขุนหลวงหาวัด) or the King Who Sought Temple.

Prince Kromma Muen Thepphiphit, the leader of the 1757 proposal, shaved his head to become a Buddhist monk at Wat Krachom temple to avoid political repercussions from the new king Ekkathat.

Prince Thepphiphit led the pro-Uthumphon conspirators to visit Uthumphon at Wat Pradu temple,[12] asking for consent and permission.

High-ranking ministers Chaophraya Aphairacha, Phraya Yommaraj and other conspiring officials were tortured, interrogated, whipped with rattan strokes and imprisoned[12] for life but not executed.

Ekkathat exiled Thepphiphit, along with his entire family, on a Dutch ship across the Indian Ocean to Sri Lankan Kingdom of Kandy or Ceylon.

[7] Due to a Burmese–Siamese dispute over a French ship carrying Mon rebels,[13] perceived Siam's support to Mon people against Burma and the Burmese king's Chakravartin[14] expansionist ideology of universal ruler, in December 1759,[13] King Alaungpaya of the new Burmese Konbaung dynasty set off with 30,000 Burmese-Shan men to invade Siam.

Ayutthayan people, elites and commoners alike, beseeched Uthumphon, who had been a Buddhist monk at Wat Pradu temple and who was considered more-capable of being king, to leave monkhood to take military commands against the invading Burmese and to save the kingdom.

On popular request, Uthumphon the temple king took of his yellow monk robes[6] and returned to the royal palace to resume powers and commands.

Uthumphon's first move was to release the conspirators of the December 1758 rebellion, including Chaophraya Aphairacha the former Chief Minister, the former Phraya Yommaraj and other pro-Uthumphon officials who were regarded as being more-capable than Ekkathat's officials and who had been imprisoned for their previous failed attempt to remove Ekkathat from the throne, reinstated to their former positions.

The former Phraya Yommaraj, who had supported Uthumphon, imprisoned for his rebellion attempt against Ekkathat and then released, was heavily injured from the battle and soon died.

In order to boost the general morale of the population, Uthumphon rode in a grand royal procession along the city walls to encourage the Ayutthayan defenders to endure.

After the Burmese retreat, Uthumphon and his elder brother Ekkathat, the two kings of Ayutthaya, seemed to peacefully coexist in the royal court for a while.

However, Uthumphon remained in yellow robes, not repeating the same action, perhaps to avoid political confrontations with his elder brother Ekkathat.

Uthumphon and other Ayutthayan royal members followed Nemyo Thihapate in the northern land route to Uthaithani, where they turned west, going through the foresty pass in modern Thung Yai Naresuan Wildlife Sanctuary through Umphang to reach Martaban.

Uthumphon and his Yodayan followers moved to the new Burmese royal seat of Amarapura, settling at Yawahaeng or Rahaeng villiage.

Upon his death, Uthumphon was entombed in a chedi at the Linzin Hill graveyard on the edge of Taungthaman Lake in Mandalay Region's Amarapura Township, about 500 metres (1,600 ft) northwest of U Bein Bridge.

[17] On 29 June 2013, Burmese and Thai authorities announced that the site of Utumphon's memorial tomb would be renovated and turned into a historical park.