Ananda Mahidol[b] (20 September 1925 – 9 June 1946) was the eighth king of Siam (later Thailand) from the Chakri dynasty, titled Rama VIII.

Although at first thought to have been an accident, his death was ruled a murder by medical examiners, and three royal aides were later executed following very irregular trials.

He briefly attended Debsirin School in Bangkok before the revolution in 1932 ended the absolute monarchy and raised the possibility that King Prajadhipok might abdicate.

Queen Savang Vadhana, his grandmother, was concerned about Prince Ananda Mahidol's safety, since he was one of the likely heirs to the throne.

However, when King Prajadhipok's abdication appeared imminent, the prince's mother was approached by a member of the government, asking for her opinion about Ananda Mahidol succeeding as monarch.

King Prajadhipok (Rama VII) abdicated in 1935 due to political quarrels with the new quasi-democratic government as well as health problems.

The law was enacted on the death of King Vajiravudh in 1925 and the crown passed to his youngest brother, Prince Prajadhipok of Sukhothai.

It was argued that King Vajiravudh had virtually exempted the prince's father from the ban in the Succession Law, and the crown might thus be passed to him.

King Ananda was away from the country, as he had returned to Switzerland to complete his studies, and Pridi Phanomyong served as regent in his absence.

Despite his youth and inexperience, he quickly won the hearts of the Thai people, who had continued to revere the monarchy through the upheavals of the 1930s and 1940s.

Foreign observers, however, believed that Ananda Mahidol did not want to be king and felt his reign would not last long.

Louis Mountbatten, Earl Mountbatten of Burma, the British commander in Southeast Asia, visited Bangkok in January 1946 and described the king as "a frightened, short-sighted boy, his sloping shoulders and thin chest behung with gorgeous diamond-studded decorations, altogether a pathetic and lonely figure".

At a public function, Mountbatten wrote: "[H]is nervousness increased to such an alarming extent, that I came very close to support him in case he passed out".

Keith Simpson, pathologist to the British Home Office and founding chairman of the Department of Forensic Medicine at Guy's Hospital in London, performed a forensic analysis of the king's death and recounted the following sequence of events on the morning of 9 June 1946:[1] An initial radio announcement on 9 June surmised that the king was accidentally killed while toying with his pistol.

[3] Following the change of prime minister, in October 1946, a Commission of Inquiry reported that the king's death could not have been accidental, but that neither suicide nor murder was satisfactorily proved.

In November 1947, Field Marshal Plaek Phibunsongkhram staged a coup against the elected government of Pridi, appointed Democrat Party leader Khuang Aphaiwong as Prime Minister, and ordered a trial.

[3] The prosecution's case was supported by 124 witnesses and such voluminous documentary evidence that defence counsel asked for an adjournment to give them time to consider it.

The court ruled that King Ananda had been assassinated, but that Chaliao had not been proved guilty and that neither of the pages could have fired the fatal shot.

The three men's petitions for clemency were rejected by King Rama IX (Bhumibol Adulyadej), and they were executed by firing squad on 17 February 1955.

On 15 June 1946, American Chargé d'affaires Charles Yost met with Foreign Minister Direk Jayanama, who had just had an audience with the new king, Bhumibol Adulyadej.

[3] In 1948, Pinit Intaratood, who had just been appointed as the police officer in charge, went to the Villa Vadhana in Lausanne to question King Bhumibol.

[8] Sulak Sivaraksa, a prominent conservative and monarchist, wrote that Pridi's role in the event was he protected a wrongdoing royal, and prevented an arrest of a person who destroyed the evidence.

[9]: 5–6  He wrote a Facebook post in 2015 claiming: "in truth, the murderer of King Rama VIII is not Pridi Banomyong.

I felt it necessary to state to both of them in the strongest terms, in order to make it perfectly clear that this Legation could not be drawn into Siamese political intrigues, that I did not believe these stories and that I considered the circulation at this time of fantastic rumors un-supported by a shred of evidence to be wholly in-excusable.

The British Minister informed me this morning that he had also been approached by several members of the Opposition to whom he had stated that he accepted the official account of the King's death and that he would not be drawn into any further discussion of the matter.

[Pridi] was violently angry at the accusations of foul play leveled against himself and most bitter in the manner in which he alleged (without doubt justly) that the Royal Family and the Opposition, particularly Seni Pramoj and Phra Sudhiat, had prejudiced the King and especially the Princess Mother against him.

The M1911 is not especially prone to accidental discharge; it will fire only if considerable pressure is applied to the safety plate at the back of the butt at the same time as the trigger is depressed.

[11] Another account, which concluded that Ananda Mahidol's death was the result of suicide, was explored by journalist Rayne Kruger in his book, The Devil's Discus.

Kruger, who had unprecedented access to members of the inner circle of the Thai royal family (although these contacts had to remain unidentified), drew the conclusion that Ananda's death was most probably an 'accidental suicide'.

Thus, said Kruger, it appears the sad, most likely accidental, death of the young king was exploited for the purposes of a political vendetta, and that three innocent victims were executed to maintain the façade.