Bhumibol was venerated for the stabilising role he played during his record-breaking 70-year reign.

Observers say Vajiralongkorn has proved his detractors wrong with his recent moves – including the swift veto of Princess Ubolratana Rajakanya’s plan to enter politics.

“Before his father’s death, many predicted that Vajiralongkorn, perceived as having lacked moral authority, could become a weak king,” political observer Pavin Chachavalpongpun wrote last year. “He is quickly proving them wrong.”

Thrice married, Vajiralongkorn is trained to fly a range of aircraft including fighter jets, helicopters and commercial jets. He saw combat in Thailand’s 1970s anti-insurgency campaign.

PRINCESS UBOLRATANA RAJAKANYA

The eldest of Bhumibol’s four children, Ubolratana was born in Lausanne, Switzerland, while her father was a student there.

Like her law-trained father, Ubolratana excelled in school and earned degrees at the Massachusetts Institute of Technology and the University of California at Los Angeles.

She relinquished her royal titles when she married an American man in the 1970s, but upon divorcing him in the late 1990s – after raising three children in San Diego – Ubolratana returned to Thailand for good in 2001. She was bestowed the title of “Toon Kra Mom”, or daughter of a reigning queen.

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The 2000s were highly eventful for the princess: she launched a career as an actress – starring in television dramas including one co-starring Hong Kong actor Shawn Yue – but faced tragedy when the 2004 Asian tsunami killed her son, Poom.

Her decision to run as a candidate with the Shinawatra-aligned Thai Raksa Chart party took few observers by surprise, as she had in the past hinted she was aligned with the political bloc’s “red shirt” supporters.

QUEEN SIRIKIT

Sirikit Kitiyakara, born to Thai nobility, married Bhumibol in 1950 after meeting him in Paris. Like her husband, she was venerated for her charity work in support of the kingdom’s rural poor.

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But in the 2000s, as the stand-off between the Shinawatra bloc and the establishment elite became more pronounced, some in the chattering class questioned – in whispers – whether she was backing the “yellow shirts” behind the scenes. Sirikit is believed to be close to the royal court’s long-term power broker Prem Tinsulanonda. Nowadays she is rarely seen in public. The palace in 2016 said she had suffered an ailment that caused her to have “insufficient blood in the brain”.

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PREM TINSULANONDA

Prem Tinsulanonda is the president of Vajiralongkorn’s Privy Council. The former army general, 98, has occupied that position for the past two decades, during which he cemented ties between the military and the royal court. He served as prime minister from 1980 to 1988, withstanding two coups and multiple assassination attempts. For many political watchers, Prem remains the face of the royalist-military establishment that reviles the Shinawatras.

While he served as a temporary regent after Bhumibol’s death – before Vajiralongkorn took over – the current king in recent years has appointed his own loyalists to the Privy Council, a move some observers say is aimed at weakening his father’s close confidante.

The king directed the junta to amend a newly drafted constitution that allows him to exercise sovereign powers even when abroad. Vajiralongkorn therefore does not need to appoint Prem as regent when he is in Germany.

PRAYUTH CHAN-OCHA

Career soldier Prayuth is the bookmaker’s pick to be prime minister after the March 24 polls, after the candidacy of Princess Ubolratana was vetoed by King Vajiralongkorn.

The 64-year-old is the preferred prime ministerial candidate of the Palang Pracharat Party that is widely viewed as a political vehicle of the junta.

He became an internationally recognised face after orchestrating the 2014 coup against Yingluck Shinawatra – the second anti-Shinawatra coup in the past two decades. Fondly referred to as “Uncle Tu” by his supporters, the junta leader has a reputation for being testy, often skirmishing publicly with probing journalists. He is part of the “Eastern Tigers” bloc of Thailand’s military, otherwise known as the Queen’s Guard.

APIRAT KONGSOMPONG

Army chief Apirat Kongsompong is the newest key player in Thailand’s Game of Thrones. The son of a former junta leader, Apirat was made army chief last September. He leads the King’s Guard bloc of the country’s factionalised military, which over the last two decades has been dominated by Prayuth’s Eastern Tigers. Apirat, analysts say, has the backing of Vajiralongkorn.

In January he was appointed to the Crown Property Bureau, which has holdings of over US$30 billion, according to one estimate. Apirat’s appointment follows Vajiralongkorn’s 2017 decision to give himself full control of the bureau. The army chief last week denied widespread speculation that he and currently active generals were planning a coup against Prayuth’s administration.

THAKSIN SHINAWATRA

Thaksin Shinawatra, 69, is the singular force behind Thailand’s past two decades of political turmoil. He has undergone multiple career shifts – from police chief to telecoms tycoon, establishment politician, and subsequently populist prime minister.

Since going into exile in 2008 – two years after the military staged a coup against him – Thaksin has pulled the strings of the rural-based political movement he started in the 2000s. The movement has won every election since 2001. In the election held after the 2006 coup, his brother-in-law Somchai Wongsawat led loyalist parties and became prime minister.

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After a brief period in which pro-establishment forces held power, the Shinawatras again returned to the apex of power – this time with Thaksin’s sister Yingluck as prime minister. It was her government that was toppled in Prayuth’s 2014 coup.

While his loyalists paint him as a champion of the poor – pitted against the pro-establishment metropolitan elite – Thaksin’s critics want him out of politics because they say he is corrupt and perpetuated cronyism during his time in power. Some of his critics say he is anti-royalist.

YINGLUCK SHINAWATRA

A mere puppet or able deputy? The 51-year-old younger sister of Thaksin has long faced criticism that she is merely a mouthpiece of her more famous brother. Still, with her brother in exile, it was the former businesswoman who held the fort for the Shinawatra movement in the 2011 elections. The Pheu Thai party she helmed – which is also contesting the upcoming March 24 polls – staged a crushing victory.

She was prime minister for three years until Prayuth seized power from her. The military staged a coup after widespread discontent at one of Yingluck’s policy moves: a proposal to grant amnesty for those found guilty of political violence in the years after her brother was ousted. It was seen as an underhanded way to allow Thaksin to return home on a clean slate.

She fled Thailand in August 2017 just before she was found guilty of “criminal negligence” while in power – a charge she says was trumped up by Prayuth’s administration. ■