THE great historian Sir Simon Schama said of the 18th century Acts of Union between Scotland and England: "What began as a hostile merger would end in a full partnership in the most powerful going concern in the world; it was one of the most astonishing transformations in European history.”

On May 6 next year, the sixth elections to the Scottish Parliament will take place and could mark another transformation: the beginning of the end for the Union of Great Britain, which Boris Johnson once proudly described as the “most successful political and economic union in history”.

The poll will effectively be a referendum on a referendum and Scots will cast their votes on brand Britannia just five days after the 314th anniversary of the Acts, that established it, came into effect.

Even if the pall of Covid-19 that has benighted our country is largely lifted by then, the lingering effects of the coronavirus will still be felt and will create an unnerving backdrop to the Holyrood campaign, which will begin in earnest next month.

If the psychodrama of Brexit and the long-running saga of the trade talks with Brussels were not enough, we have had the grim soundtrack of the pandemic to highlight cross-border differences that have played into the politics of identity.

READ MORE: Support for Scottish independence at 52 per cent in new poll

After the differentiation between Scotland and England on Brexit came the differentiation on how to tackle Covid-19; facilitated by the devolved settlement that meant most health matters were now decided in Edinburgh not London.

Indeed, Nicola Sturgeon’s slick media performances contrasting with the, at times, Woosterish appearances of the Prime Minister have, for some, underlined how Scotland and England handle things differently and are going in different directions politically.

Of course, difference has always been there in the relationship between the two nations; even with the creation of the Union in 1707 each continued to have distinctive legal systems and churches not to mention, later on, football leagues.

Indeed, the Scottish Parliament was only created in 1999 because, by and large, Scots voted in a different way - ie not Tory - to the English; if Scots had continued to vote Conservative, then the Blair Government might never have proposed bringing in the devolved legislature.

Now, with new leadership, Labour is banking on devolution again. It is setting up a review body under the guidance of Gordon Brown as part of a proposal for a “new partnership” of full federalism to save the Union.

In a recent keynote speech on the subject Keir Starmer insisted the Union had been and could be again a “great force for social justice, for security and for solidarity”.

With Labour having for so long been stuck between the two poles of pro-independence Nationalism and pro-Union Toryism, the Leader of the Opposition argued Scots did “not have to choose between a broken status quo and the uncertainty and divisiveness of separatism”.

Devo-max, as it was once called, could, Sir Keir suggested, provide a “positive alternative”. And, no doubt, he hopes it will help propel him into Downing St.

Yet as things stand, there will almost certainly be a pro-independence majority at Holyrood come May 7 and, possibly, an SNP one.

The polls have for some time now been pointing in one direction. Since March, there have been 17 consecutive surveys placing the Yes camp ahead. Earlier this month, one put it 14 points clear on 52% to 38; its highest lead to date.

Don’t-knows are invariably nowadays left out from the polling statistics to enable the media to give clear numbers on who is for and who is against. Yet, arguably, the don’t-knows are the most important people.

In 2014, it was the don’t-knows, who fell largely back to the devil they knew and backed the Union, helping to give the No camp its 55-45 point lead. Of the snapshots this year, the don’t-knows were between six per cent and 14. Indeed, the latest poll, which gave the Yes camp its largest lead to date, had don’t-knows at 10%.

READ MORE: Two-thirds of SNP voters want Covid recovery before Scottish independence referendum

So, the uncertainty factor could still play a big, if not decisive, role in the result of any second referendum.

At present, the unknown unknown is: does the continuous poll lead in support of Scottish independence mean the constitutional axis has shifted for good? Or, can the Unionist cause revive itself and shift the dial in favour of maintaining Great Britain?

Of course, one key question remains: will indyref2 ever happen?

A Survation study for the Scottish Labour Party this month suggested almost eight out of 10 Scots wanted the SNP Government to prioritise dealing with the economy and Covid-19 over its attempt to get a second independence referendum. Indeed, nearly two-thirds of SNP supporters agreed.

While Ian Blackford, the Nationalist leader at Westminster, has insisted indyref2 “must” happen in 2021, Ms Sturgeon has hedged her bets, telling the SNP conference last month she wanted one in the “early part” of the next Holyrood Parliament, which could mean any time between autumn 2021 and spring 2023.

The First Minister has confidently declared: “If people in Scotland vote for a referendum, there will be a referendum.” In other words, if the SNP won a majority in May, then Mr Johnson would be honour-bound to facilitate another vote on Scotland’s future.

The legal eagle Joanna Cherry, regarded as a prominent ally of Alex Salmond, has suggested, even though the constitution is reserved to Westminster, the Scottish Parliament could itself legislate for another referendum and take its chances in the courts.

If Ms Sturgeon gets her Holyrood majority in May, then SNP tails will be up and Mr Johnson will face three options: the ‘oh, alright’ option; the ‘no, nay, never’ option or, in the midst of Covid, the ‘now is not the time’ option.

The first is highly unlikely given all the PM has said up to this point; although Boris is proving to be a master of the U-turn. The third option, echoing Theresa May’s mantra, might be the choice of words he uses given, as the Survation poll has suggested, this is the course even most SNP supporters favour; yes to indyref2 but not just yet.

But, of course, politics has a habit of changing quickly; parties can be up one moment and down the next; and vice versa. There are and will be colleagues of the FM telling her that a window of opportunity only stays open for so long.

While one can paint a scenario where Mr Johnson is under such intense political pressure that he ultimately caves in, there could also be one where he digs in, hoping for the political pendulum to swing in his favour. After all, he does not want to become the Lord North of the 21st century; forever millstoned as the PM who lost the “precious Union”.

If a Brexit trade deal were done and things ticked along reasonably well in 2021, the mass vaccinations began to restore life to a near-normality, growth returned, job numbers started to rise, people enjoyed a holiday again, the Euro football championships took place over summer, then a feelgood factor might at last return.

The political fall-out to the Salmond case has yet to unleash itself in any significant way but could do so next year, plunging the SNP into more recriminations just as the Tories begin to rally behind Mr Johnson and the political honeymoon, the PM never had, suddenly emerges.

The Tory leader, who has styled himself as Minister for the Union, has established a Union Unit in Downing St. At first, just a small team, we are now led to believe it will be expanded.

Alister Jack, the loyal Scottish Secretary, has spoken of developments about strengthening the Union, although these are yet to materialise.

The Dunlop Review on “strengthening the Union” – on the PM’s desk since December 2019 – and the intergovernmental review on improving relations between London and Edinburgh were due to be published in November but have now been pushed forward to 2021, forming part of what one Tory insider described as a hopeful “brave new dawn” post a Brexit trade deal and a decline in the coronavirus induced by mass vaccinations.

It is now possible that the publications of the reviews will form part of the UK Government’s lead-in to the Holyrood election in May and as part of a Conservative “2021 reset”.

Mr Johnson recently offered his opponents an early Christmas present, branding devolution in Scotland a “disaster”; he later clarified his remarks, insisting what he had meant to say was that it was the SNP Government’s handling of devolution that had been calamitous.

Mr Jack has suggested the controversial UK Internal Market legislation will enable Whitehall to directly fund projects locally in Scotland, thus bypassing Edinburgh and providing “real devolution,” as the Secretary of State put it.

The passing of the Bill saw the usually undemonstrative SNP MP Drew Hendry “doing a Hezza” and protesting in the Commons chamber by picking up the mace.

So, despite the travails of sorting out a Brexit trade deal and battling coronavirus, the issue of whether to stick with or abandon the 300-year-old Union goes on and will percolate to the top of the political agenda in 2021.

If indyref2 were to happen by 2023, then the ground campaign would be much more acrimonious than that of 2014, simply because the stakes would be that much higher; it would pit the pro-UK Unionists against the pro-EU Unionists.

The old subject matter would be revisited, most particularly the economy.

Scotland’s notional deficit of 7% of GDP is roughly seven times higher than that of the UK as a whole; proof, say pro-Unionists, that an independent Scotland would struggle and face years of austerity. But the pro-Independents insist the bad numbers simply underline the need for Scotland to break free of the UK and set its own priorities.

With the UK borrowing at record levels, surely an independent Scotland could simply do the same?

Yet if the Yes camp were to lose again, it would almost certainly set its cause back for a generation while a victory would change politics across these islands forever; once the departure dust had settled, Great Britain would, to all intents and purposes, simply cease to exist.