For years now, Saudis and Emirates have expressed frustration over Qatar's foreign policy. The current diplomatic rift has its roots in the 2011 uprisings in the Middle East and North Africa, where Qataris refused to toe the Saudi line.
Panic has gripped the Middle East. And, for once, it has little to do with Daesh, Al Qaeda or Israel.
Saudi Arabia, the United Arab Emirates, Bahrain and Egypt, boycotted Qatar on Monday morning, severing diplomatic ties and asking Qatari citizens to leave their borders within a fortnight.
Later, Yemen and the Maldives mirrored the move against Qatar.
The boycott is not only diplomatic. It's also economic: Qatar Airways is barred from entering the air space of the estranged Gulf nations. The naval waters have also been closed for Qatar.
The tussle is rooted in the early 1990s but after decades of friendly calm it resurfaced with the popular uprisings in the Middle East and North Africa, where the foreign policy of Saudi Arabia often mismatched with Qatar's.
Qatar has also tried to resist Saudi-led counterrevolutionary moves after the Arab uprising.
A similar diplomatic row between the two energy-rich nations erupted in 2014, when Doha attempted to take a different foreign policy approach toward Egypt – one which wasn't aligned with Saudi Arabia's and other Gulf allies'.
The country-wise breakdown of the crisis:
In 2014, former army chief Abdel Fattah el Sisi won the presidential election by a landslide.
Sisi had led a coup the previous year and toppled the democratically elected government of Mohamed Morsi, the leader of the Muslim Brotherhood, a populist movement with strong religious undertones.
Saudi Arabia, where powerful monarchs have held sway for decades, bitterly opposed the Muslim Brotherhood, along with its close allies, UAE and Bahrain.
The Brotherhood's aim is to end military dictatorships and decades-old monarchies, and they use democracy as a tool to make political gains.
Most of the Gulf states view the Brotherhood suspiciously and have carried out several crackdowns against its members. In 2013, the UAE arrested 11 Egyptians, accusing them of recruiting people into the organisation.
Contrary to other Gulf countries, Qatar backed the Brotherhood to the point that it made Sisi's government repay billions of dollars of aid, which the country had given to the ousted Morsi administration.
By then, Riyadh was already displeased with Qatar and the Arab uprising in 2011 that saw strongmen being replaced by elected representatives in Tunisia and Egypt. Now Qatar giving a cold-shoulder to Sisi embittered Saudi leaders further.
As a result, Saudi Arabia and the UAE called back their ambassadors for several months.
When protests swept through North Africa and the Middle East in late 2010 and early 2011, Al Jazeera, Qatar's state-broadcaster, reported the events relentlessly.
After a long time, Tunisian dictator Zine el Abidine Ben Ali was forced out of power. He fled to Saudi Arabia and the new Tunisian government has since been asking for his extradition.
During the days of revolution, the then-Emir of Qatar Sheikh Hamad bin Khalifa visited Tunisia to celebrate the new political leadership, offering them financial aid of several million dollars.
Qatar, however, didn't support all the uprisings in the Middle East. It stood with Saudi Arabia to crush popular revolts in Bahrain and Oman.
And Al Jazeera was at play here as well, notes Tarek Cherkaoui, the author of "News Media at War: The Clash of Western and Arab Networks in the Middle East".
"Qatar contributed forces to help suppress the uprising in Bahrain, and Al Jazeera refrained from providing coverage of the repression. This was peculiar considering that Al Jazeera has championed practically every other uprising in the Middle East," he said in a research paper.
Though Saudi and the UAE is accusing Doha of promoting terrorists – a charge it denies – it supports the Saudi-led coalition fighting the Houthi rebels in Yemen.
The uprising that led to the departure of Muammar Gaddafi was actively backed by Qatar and the UAE, along with most Western powers.
The UAE also supported the campaign against Gaddafi. Soon after his fall, though, Emaritis began to disagree with Qatar's interventions. Qatar alone contributed six of its Mirage jets to a NATO-led coalition against the Libyan dictator.
Now they back opposing sides in a proxy war that has divided oil-producing Libya, plunging it into a perpetual conflict.
Qatar and Turkey back a loosely-knit Muslim Brotherhood-led coalition that controls Tripoli and the west of the country, while a UN-recognised government based in Tobruk, near the Egyptian border, is supported by the UAE, Egypt and Russia.
Lately, the UAE has had an upper hand as it backs general Khalifa Haftar, whose forces are fighting the Qatari-backed government in Tripoli.
Yemen and Syria
Qatar's Al Jazeera initially gave air time to protests that swept through Yemen against President Ali Abdullah Saleh.
At the time, Saleh had complained against the coverage of protests, saying it "only serves the Zionist entity."
Qatar's foreign policy for Yemen and Syria soon fell in line with its neighbouring Gulf partners, Saudi Arabia, the UAE, Bahrain, Oman and Kuwait. All the six countries form a conglomerate called the Gulf Cooperation Council (GCC).
In Yemen, Doha is part of the Saudi-led military alliance fighting the Houthi rebels, who are followers of the Shia sect and backed by Iran.
In Syria, GCC member states, including Qatar, are supporting the forces fighting against Bashar al Assad's regime.
The Saudi allegations that Qatar "embraces multiple terrorist and sectarian groups" and promotes "the message and schemes of these groups through their media constantly" are not new.
When it comes to Palestine, Qatar has hosted senior Hamas leaders while Saudi Arabia and the UAE supports their political rival, Fateh. Qatar has given refuge to Muslim Brotherhood leaders for years. It also played a mediator's role in Afghanistan, even letting the Taliban open up an office in Doha.