THE idea of Britain is “at the end of the road” with successive polls showing support for Scotland leaving the UK “not a normal situation”, according to a leading historian.

Stuart Ward, professor of ­British imperial history at The Saxo ­Institute, University of Copenhagen, also said it was “obvious” that UK Prime ­Ministers were rejecting another ­independence referendum because they “don’t trust people to invest their hearts in the Union”.

And he argued the death of Queen Elizabeth and accession of Charles III will also accelerate the end of Britain.

The conclusions come in a new book based on 10 years of research and travel spanning places such as the UK, Ireland Australia, Kenya, ­Zimbabwe and Hong Kong, which aims to place the debate over the break-up of Britain in a wider ­historical and geographical context.

Speaking ahead of the publication of Untied Kingdom: A Global History Of The End Of Britain next month, Ward told the Sunday National: “The idea of being British and the ­unravelling of that idea over the best part of the last 100 years, that is a ­story that needs a wide-angle lens.

“I went out to not only try to ­experience first-hand the historical geography of Britishness but also ­because the source material for this is so scattered and diverse.

“I was visiting public libraries, I was visiting manuscript collections, archives and so forth to see if I could pull together a coherent story about why Britishness as a civic idea, as an idea of the people, became unstuck, as a means to contributing to the ­ongoing discussion about the fate of independent Scotland or otherwise.”

Ward said he had come to the conclusion that Britain is in its end stages because all ­political communities need to have an “emotional foundation”.

He said the idea of Britishness had emerged with the expansion of the empire, but that has been slowly ­eroding over the decades.

“It is hard to see how it is going to ­reconstitute itself in the ­contemporary United Kingdom,” he said.

“One of the things that was often levelled at the Better Together campaign in 2014 is that it was criticised for lacking in emotional content – that it went after the fire and brimstone.

“But it is much more difficult to devise what those emotional arguments are likely to be when the unifying emotional prism has fundamentally cracked.”

He said polls recording upwards of 50% of people of any community wanting to “be something else” could not be sustained over the long term.

“I think in the UK people have ­started to lose a sense of how ­abnormal that is – every two or three months there is another poll about do you feel more British or English, do you feel more British or Scottish, Welsh,” he said.

“This has almost become a ­parlour game without people pausing and saying ‘hang on a moment, this is extraordinary’.

“I am from Queensland, which is an extremely parochial state – I have never seen a poll asking: ‘do you feel more Queenslandish or Australian?’

“The questions would be meaningless because the concepts actually fit together.

“So we have lost a sense of just how abnormal that is, for starters, and we have also lost a sense of how ­unsustainable it is.”

He added: “That would apply to a nation-state, that would apply to a yacht club, that would apply to a crochet society – any group or club where half of its members on and off depending on the day say I’d rather be part of a different unit.

“That does not have longevity on its side, particularly because the numbers have been accelerating over time.”

Ward said it was the decline of the empire that had marked the rise of a new political force in the shape of the nationalist parties, including the SNP and Plaid Cymru.

He argued the current ­constitutional impasse in Scotland was not unique, comparing it to the campaign for ­Australia to become a republic which has yet to succeed.

“The problem is getting ­coherence and consensus around where you want to be, because of the very ­minute that you get a bunch of ­people in the room to say I think we need to get ­beyond Britain, you’re not necessarily going to get them into a place where they’re going to agree on where that is going to go,” he said.

“There is the SNP’s internal ­problem of actually trying to get the party and the cause to move in the same direction.”

But he added: “For whoever is the occupant of Number 10 to just say ‘now is not the time and the ­referendum doesn’t happen’, that I think is not a sustainable position by any means.

“I think at some point, the ­electoral arithmetic will change in the ­Commons possibly in the SNP’s favour, where there will be more ­leverage of some sort.”

WARD also pointed to the succession of Tory prime ministers who have refused a second independence referendum in Scotland on the basis the issue had been resolved in 2014.

“It’s obvious that the only ­reason that they don’t do what David ­Cameron did is that unlike Cameron, they don’t trust the people to invest their hearts in the Union,” he said.

Ward said that the late queen had been the first monarch to travel widely and epitomised the idea of a global Britain that was expansive and was not “confined by the laws of geography”.

“The way in which she could ­reassure the citizens of the ­United Kingdom that there is a place ­elsewhere where we as a people ­resonate globally – I don’t think any of her successors is going to be able to do that,” he said.

“I think the fact the monarchy, particularly with Elizabeth’s passing the monarchy can no longer pull that off, just adds another sort of notch on the on the milestones towards the break-up of Britishness as we’ve known it.”

Ward said viewing recent ­political events from a wider global and ­historical perspective of how the ­Empire has unravelled, showed how far down the road Britain has come – concluding it is “really at the end of the road at the moment”.

He said: “All of these different parts of the world, where there were strong constituencies that were ­heavily ­invested in the idea of an overarching attachment to something larger, they have all come unstuck.

“So I’m looking for a reason why it should stop in Scotland, or Wales or wherever else.”