Brexit has illuminated and inflamed long-fomented divisions within British society, between England and its Celtic fringe, London and the rest of the England and young and old.  Our national story has never been so contested, so divided from itself.  We need voices in public life that can begin to pull off an incredible paradox – how to weave together a tapestry that has been so completely unpicked?

The lines are drawn: the order of battle set.  We have the ecstatic vision of the hard Brexiteers.  Here is Jacob Rees-Mogg: “This is Magna Carta, it’s the Burgesses coming at Parliament, it’s the Great Reform Bill, it’s the Bill of Rights, it’s Waterloo, it’s Agincourt, it’s Crécy.  We win all of these things.”  Brexit is Britain once more in its first flower, a victory home and abroad, past, present and future.

And then the sneer of the hard Remainers: Martin Amis on the Today programme last week saying Brexit is “the return of just the sort of England I don’t like: the country town, rustic, beer drinking, family butcher England”.

And as for the promise of the Prime Minister’s British Dream…

A staging of Purcell’s opera, King Arthur, a co-production by the Barbican and the Academy of Ancient Music, attempts to meet this question head on, pitched as ‘art in the age of Brexit’.  Early music is rarely associated with a direct dialogue with overtly political themes.  It depends on a more limited vocabulary than the modern orchestra, with its weight and complexity, often depending solely on four or five lines of counterpoint.  In the clear world of Bach, Palestrina and Byrd, we encounter a people who do not know that life could be different to the present, before modern man is pressed down by Milan Kundera’s “sudden density of time”.

In conversation with the Director, Daisy Evans, I am corrected: “King Arthur can’t be done as a nice evening’s concert.  It can’t be a nice evening’s entertainment.”

Pre-modern purity be damned, she continues: “We’ve become horrible bigots and we read papers that encourage us to fight each other.  We need a clear voice that says we must fight for England.  We must be strong and honourable.  We can be better.  There is a divide between men and women, between left and right, and between leave and remain.  Within these little vignettes, the audience can make a decision on what side they come down on.”

King Arthur was commissioned as a light piece for the entertainment of the court.  The semi-opera was a highly demotic form, including drinking songs alongside more formal choruses and arias.  And Evans pushes it to its limits.  To create this better vision of England, Evans takes an opera that unashamedly celebrates the victory of a mythical force of native Britons over the vile foreigner – the Anglo-Saxon invader – and reworks it into an intriguing set of reflections on Britain’s modern past and present.

The ‘on trend’ conceits, designed to replicate the ‘folly’ atmosphere of the sixteenth century drama, felt at first forced: the cast emerges from the audience, busy on their smartphones, and spend the first chorus taking selfies.  Cringe-making billboards stand at either side of the stage, with up-to-date tag lines – “A polling booth”, “Today”, “The Barbican” and even “Idea and Reality”.

But the boldest move in the production actually pays off really well.  Dryden’s original text is jettisoned virtually wholesale.  Made up of endlessly bland refrains: “The British Wool is growing gold”; praise for “the honour of Old England”; “Fair Britain all the world outvies”; “Let Britannia rise”; and the climactic “Fairest Isle, all isles excelling.”  The Mogg-like immaturity of Dryden’s text is thrown into stark relief by the selection of poems and texts that intervene when the music falls silent.  Read by a narrator who stands above the competing factions – the wonderfully charismatic Ray Fearon – we are given everything from Bukowski, Shelley and Blake to T.S. Eliot.

This brings a seriousness and depth that the elemental and boisterously violent Dryden plainly lacks.  And the more we hear, and the more Dryden falls silent, the richer the effect becomes.  Dryden’s exaltations of martial valour pass through an endlessly refracting prism: ‘Let Britannia Rise’ is juxtaposed with Bukowski’s reflections on homelessness; ‘Fairest Isle’ with the halting repetitions of Eliot’s Hollow Men: “This is the way the world ends.”

Evans says: “We are trying to redefine what Britannia is.  It should not be right or left.  Gentleness, joy and love, these are our virtues.  We do not need empire; we can create a new empire out of these old virtues.”

It is hard to talk about a British community ideal – in contrast with France or America.  The British identity has never been shaped by a single vision, or a single historical event, but in a curious way has always been constituted by its divisions, between left and right, between Whig and Tory, between the Shires and the Metropole, and Brexit is yet another iteration of this schizophrenic tendency.

But we must always yearn for some gentle vision of Britain that no longer wishes to confront and divide itself, but to heal.  And I think that this ethic sits well in the unrestrained beauty of Purcell’s settings, which always hover above the competing storylines and references introduced by the modern texts.  In a sense, I want to come back to my vision of early music and the pre-modern – a world in which only a few voices exist, united by Purcell’s plangent harmonies.  And a world in which the words ‘leave’ and ‘remain’, ‘hard’ and ‘soft Brexit’, ‘no deal better than bad deal’, ‘Brexit means Brexit’, ‘go global’, ‘take back control’ had never been heard …