And so the great unravelling begins.

Predictably, there were early attempts to try to soften the impact — and stem the stunning financial repercussions — with soothing words about stability and continuity.

But no words could cushion the immediate and seismic consequences of Britain's sobering rupture with the EU Friday.

At home, people woke up to political change happening in just hours that would normally require years.

'David Cameron will go down in history as the man who by mistake took us out of the EU.' - Tim Bale, professor of politics, Queen Mary University of London

Internationally — beyond the regret and disappointment of EU officials — the potential consequences prompted leading geopolitical expert Ian Bremmer to describe Brexit as "the most significant political risk the world has experienced since the Cuban Missile Crisis."

With all that as a backdrop, by midday, Britain was not only worryingly polarized but also well into the process of a massive political correction — all precipitated by the dicey actions of its prime minister.

The referendum Prime Minister David Cameron had promised would settle a rift within his own Conservative party had by this morning created a multitude of rifts.

Cameron's giant gamble also now looks set to be the undoing of two unions: one of which he tried to salvage in vain and the other is the country he will soon no longer lead.

"David Cameron will go down in history as the man who by mistake took us out of the EU," said Tim Bale, an academic and expert in British and European politics who teaches at Queen Mary University of London.

"[Cameron's] career finishes in failure where it might have finished in success."

The man who saved Scotland now facing even bigger unravelling

It is near impossible to imagine the turmoil in Cameron's mind as his own career unravelled and the prospects for his party wavered after he announced he would resign by the fall.

His voice occasionally catching, Cameron said he would leave it to the next prime minister to negotiate the terms of a Brexit from the EU.

Prime Minister David Cameron resigns0:23

It would have also been tough for the man who gambled — and won — in holding a Scottish referendum to now recognize he has made the prospects of the country's unravelling more real than ever.

As if on cue, Nicola Sturgeon, Scotland's first minister, appeared shortly after Cameron's speech to publicly announce her government would begin drafting legislation on a second referendum on independence from the U.K.

Nicola Sturgeon threatens new independence referendum0:38

Given the overwhelming desire of Scottish voters to remain in the EU, a second try has a much better chance than the first to be successful.

"I am absolutely determined in my responsibility to give effect to how Scotland voted yesterday," she said while insisting there would be consultation first.

Britain's political class seizes the moment

From the moment it seemed Leave would prevail, a parade of the United Kingdom's political class seemed to rewrite the rules: Sinn Fein's leader, Gerry Adams, also called for a referendum — on uniting the Irish.

Sinn Fein calls for Irish unification following Brexit0:48

Nigel Farage, leader of the United Kingdom Independence Party, was suddenly no longer a fringe force but one with significant backing. For Farage, who actually served as a member of the European Parliament, Brexit was a lifelong dream now brought to fruition with the help of millions of others who'd bought in.

UKIP leader Nigel Farage pleased with results0:23

Overnight, Boris Johnson went from a bombastic, dishevelled former mayor with rumoured grander ambitions to Cameron's (still dishevelled) obvious heir apparent. Unlike his fellow Brexiter Farage, Johnson gave a sombre speech that was uncharacteristically charitable — perhaps even an attempt at sounding prime-ministerial.

Britain EU Photo Gallery

British Prime Minister David Cameron gambled on a referendum he hoped would unite his party and the country but ended up creating even more rifts, writes Nahlah Ayed. ((Stefan Rousseau/Associated Press)

But while the biggest headline, beyond the referendum result, was the prime minister's decision to resign by the fall, he wasn't the only politician to watch his political fortunes plummet with the value of the pound.

Labour Leader Jeremy Corbyn's leadership was challenged this morning by some party members unhappy with his lacklustre performance in the Remain campaign. There could well be a leadership challenge there, too, in a party that has struggled with its choice of leader from the start.

Polarized electorate

Watching all this, thanks to the referendum, is one of the U.K.'s biggest ever and most-polarized electorates.

Perhaps one of the most significant rifts created here is that between the country's young and old, who were on opposite sides of the debate, with the youth favouring remaining in the EU.

What that demographic rift might mean for the future of this country is not yet fully appreciated, but it's hard to imagine it being good.

Regardless, by fall, the U.K. could have a new prime minister, a new opposition leader, perhaps even a new party—and a looming election.

All this, before it even begins negotiating with that other unraveling union — while everyone holds on for dear life.​

With files from Tracy Seeley