The backdrop to all these political bombshells was the oil-rich Kingdom of Saudi Arabia, and the heightening of its bitter struggle for regional primacy with the Islamic Republic of Iran.

The mercurial 32-year-old Saudi Arabian Crown Prince Mohammed bin Salman has upended the kingdom's long tradition of putting stability first, setting off a series of geopolitical tremors that have ensnared the kingdom's Gulf neighbour Qatar, a battered Yemen and now - it would seem - an already fragile Lebanon.

Saudi Arabia formally became a nation-state after Abdulaziz al-Saud united disparate kingdoms and emirates in 1932. The discovery of oil in 1938 gave King Abdulaziz, also known as Ibn Saud, unrivalled political leverage in the region as multinational companies poured in.

After the death of King Abdullah - one of Ibn Saud's 45 sons - in 2015, his half-brother King Salman came to power signalling a more muscular foreign policy to deal with the aftermath of the "Arab Spring". He launched a major invasion of Yemen, the poorest Arab country, with US support in March 2015 and has led a Gulf boycott of Qatar for its funding of militant groups and its backing of the controversial TV station al-Jazeera.

More importantly, he installed his son Mohammed as heir to the throne in June this year to enact a bold domestic agenda that has included allowing women the right to drive.

Domestic troubles

In May this year the supremely confident MBS, as he is known, gave an interview trumpeting his anti-corruption credentials. Part of his ever-expanding portfolio is heading Nazaha, Saudi Arabia's fledgling anti-corruption commission.

The Crown Prince had been confidently talking about cleaning up house and turning the conservative kingdom into an attractive investment destination, but there was little indication that his campaign would become a royal purge of epic proportions.

"No one will be spared if they are involved in corruption, whoever they are, no one will be spared whether they a minister or an emir [prince] or anyone ??? they will be tried," he said, in a recent clip that is being shared widely among Saudi social media users.

The move to imprison several prominent members of the royal family in Riyadh's Ritz-Carlton has been portrayed in international coverage as either a maniacal power grab or a genuine attempt at implementing ambitious reforms rapidly as Saudi Arabia deals with falling oil prices while embarking on grand national projects such as Vision 2030.

So far, over 200 officials - including the 11 princes - have been arrested, with investigators noting they uncovered at least $US100 billion in illicit funds.

"MBS has probably got two objectives: one is to seize as many instruments of power, consolidating it, and the second is to either root out significant sources of corruption or convey the image [that] that's what he's trying to do," says Robert Jordan, a US ambassador to Saudi Arabia under George W. Bush.

"He has a certain impetuous streak about him," Jordan added.

MBS has been lauded in Western coverage for being a single-minded reformer ushering in more liberal policies domestically. He has burnished his image internationally with interviews to The Guardian and The Economist in recent months.

Bernard Haykel, a Princeton University professor who has written extensively about Saudi Arabia, is positive in his assessment of the young prince.

"I have no doubts that he has intentions to reform the kingdom because he sees oil as a resource that's losing value ??? it's pretty clear that the writing is on the wall, that Saudi Arabia has to reform," Haykel told me.

"I think the only way to discipline the [royal] family is to jolt them ??? Look, he hasn't killed anyone, which he can easily do if he wanted to," he added.

When pressed on Saudi Arabia's shocking record of imprisoning dissidents and beheading citizens, Haykel described him as an authoritarian with a reformist mindset

"I see a guy who wants to reform his country and wants to consolidate his power just like Xi Jinping has done in China and [Vladimir] Putin in Russia," he added.

The Chinese 'Flies and Tigers' anti-corruption drive targeting high-level officials was also used by Robert Jordan as a comparison for how Saudi Arabia was intent on cementing its regional hegemony by diversifying its economy.

MBS's domestic moves, though, seem to be more a matter of shoring up his power base through centralisation.

"There's no question that there's a really extensive purge going on ??? that is effectively restructuring the entire power centre ??? from a system of fiefdoms to a nationally-based government underneath the power of [King] Salman and his son," said Kristin Diwan, a senior scholar at the Arab Gulf States Institute in Washington DC.

Regional instability

This centralisation can also be seen in Saudi foreign policy. The Kingdom has been one of the largest funders of counter-revolutionary political movements in Egypt and Bahrain. It has also been engaged in a geopolitical tussle with Iran through different proxy wars.

Shiite militia fighters walk along the Syrian border outside al-Badi, Iraq, earlier this year. Photo: New York Times

Iran's sphere of influence has also widened in recent years. Its longstanding funding for the Lebanese Shiite group Hezbollah and concomitant support for the Assad regime in Syria has been added to as it reinforces the Iraqi army and Shiite militias in their fight against Islamic State and provides logistical support to the insurgent Houthis in Yemen.

MBS and his father have responded to the challenge of Iran by promoting nationalism.

"There's a strong new nationalism that is emerging ??? it's a way to mobilise that is attached to the direct leadership," Diwan explained.

This was on display when Saudi officials directly accused Iran of orchestrating a ballistic missile launched from Yemen by the Houthis which targeted the King Khalid International Airport in Riyadh.

Lebanese Prime Minister Saad Hariri at a military funeral in September. On November 4 he announced his resignation, slamming Lebanon's Hezbollah group and warning that "Iran's arms in the region will be cut off". Photo: AP

Similarly bellicose rhetoric was deployed towards Lebanon, and specifically Hezbollah, after Lebanese Prime Minister Saad Hariri declared his resignation while visiting Riyadh, in what seemed a carefully choreographed statement on television.

Hariri, who is a dual Lebanese-Saudi citizen and son of assassinated former prime minister Rafiq Hariri, acquiesced to forming a barely functioning unity government with Hezbollah late last year.

There have been concerns that Lebanon could become the latest venue for the proxy war between Riyadh and Tehran, with the Houthis in Yemen managing to hold steady against a Saudi-led coalition and Sunni rebels in Syria being pushed back after Iran, Russia and Hezbollah came to the defence of the Assad regime.

Iran's President Hassan Rouhani, right, shakes hands with Vladimir Putin during their meeting in Tehran on November 1. Photo: AP

"Iran's leadership is in a tight spot domestically so it wants to enter into a war in order to unify the masses, but the [Saudi] kingdom will prevent it from doing this" said Anwar Eshki, a former general in the Saudi armed forces who also served as an adviser to the royal family.

"We are dealing with them as if we are in war, meaning political and diplomatic relations only but not a full-fledged military conflict," Eshki said, referring to Hezbollah and Iran by extension.

The whereabouts of Hariri continue to dominate Lebanese political talk shows and conversations on the street. Beirut believes that Riyadh is holding Hariri against his will, in a de facto imprisonment. There have been calls for him, including by Hezbollah and Hariri's own party, to return and officially resign in order not to plunge Lebanon further into a political quagmire.

As speculation reached fever pitch last week on Arab social media, a photo showing a fatigued Hariri next to King Salman appeared on the Saudi-controlled al-Arabiya channel, apparently aimed at calming tensions.

"There is nothing that could surprise me anymore" said Marwan Kraidy, a Penn University professor who is an authority on Arab media. "You have an acceleration of everything having to do with Saudi politics ??? I have no doubt that Hariri's resignation was a Saudi decision, not his."

Riyadh has also called upon its citizens living in Lebanon to leave the country. Kuwait, Bahrain and the United Arab Emirates have followed suit. The Gulf states have over $20 billion in investments in Lebanon, according to Saudi media, and there are fears that economic sanctions might be the next move for an emboldened leadership.

Hassan Nasrallah, the leader of Hezbollah, on a billboard in Beirut. In recent years, Hezbollah has evolved into a regional power thanks to the Syrian and Iraqi conflicts. Photo: New York Times

Daniel Shapiro, a US ambassador to Israel under president Barack Obama, went so far as to suggest that the resignation of Hariri and the escalation of rhetoric against Hezbollah were a sign that Saudi Arabia was keen to see renewed conflict between Hezbollah and Israel, in the hope that the powerful Shiite militia, one of Iran's most feared allies, would finally be cut down to size.

It is an open secret in the Middle East that Saudi Arabia and its allies - particularly Jordan and Egypt - as well as Israel itself were bitterly disappointed by the outcome of the last such confrontation in the northern summer of 2006.

Princely problems

Even as the spectre of regional conflict loomed, unverified videos of beds with colourful blankets laid next to each other in a glittering ballroom at the Ritz-Carlton animated discussions on Arab social media of how the imprisoned princes were being treated.

One of those caught up in MBS's crackdown is Prince Mutaib bin Abdullah. Once regarded as a contender for the throne during his father's reign, he headed up the powerful Saudi National Guard and has extensive business holdings including a luxurious hotel in Paris.

In December 2016, he met with Australian Defence Industry Minister Christopher Pyne to discuss potentially lucrative deals involving the expansion of the Saudi navy's capabilities using Australian defence expertise.

Although Prince Mutaib was not specifically linked to corruption in Arab media before, Diwan said that Saudi elites operate in patronage networks benefiting from business fiefdoms that they create for themselves.

Christopher Pyne meets Prince Mutaib bin Abdullah in Riyadh in December 2016. The prince is now under arrest. Photo: Twitter @cpyne

She believes that his overthrow was a combination of political elimination and consolidation of various security agencies that were on his watch under the umbrella of the National Guard.

"Prince Mutaib from the beginning was going to have a target on his back from the current [royal] generation," she said.

Even more sinister was a helicopter crash near the Yemeni border that killed eight government officials, including Prince Mansour bin Muqrin. The strange timing and lack of transparency from the authorities have raised fears that the royal purge might have taken a lethal turn. Prince Muqrin bin Abdulaziz, the father of the deceased prince, was himself ousted from the succession when King Salman took power in 2015.

Also among those arrested is Prince al-Waleed bin Talal. One of the world's richest men, with a fortune estimated to be around $US16 billion, he has invested billions in global companies such as Apple and Twitter. His arrest came as a shock to many investors and observers as he has traditionally been a regime loyalist.

"I actually met with al-Waleed in April and found him very supportive of the regime so it's mystifying but ??? his financial tentacles reach far and wide and there is talk that he opposed the appointment of the Crown Prince ??? and that they needed to take pre-emptive action against al-Waleed because of a feeling of distrust," Robert Jordan said. "This is like going after Bill Gates or Warren Buffett."

Prince al-Waleed is only one of a slew of prominent tycoons with media holdings in Lebanon who are imprisoned, a sign that the kingdom is also looking to control how these events are covered.

"I call this the Saudi-Lebanese connection in forming media operations since the '50s," said Kraidy. "But now you have the three biggest media moguls in Saudi Arabia ??? sitting in the Ritz-Carlton."

As Lebanon and Saudi Arabia continue to trade rhetorical barbs, there are real fears that a new conflict might erupt in a region wracked with instability, adding to a violent geography marred by tens of thousands of people dead and millions displaced.

"Saudi Arabia feels it's not in a good shape in Yemen, it's not in a good shape with Qatar, it's not in a good shape in Syria ??? so Lebanon goes back to its traditional role as a proxy battle ground ??? This is a worst-case scenario," Kraidy told me.