IT IS now three years since Neil MacGregor stood down as director of the British Museum (or the BM, as he calls it). And, yes, he says, there are things he misses about it.

“People talk a lot about what it means to leave an institution,” he tells me as we sit in the office of his London publisher, sipping tea. “Obviously, you miss the colleagues terribly. And I miss that wonderful sense of perspective of walking around that building every day. To start a new day with Rameses the Second puts accounting problems into a proper perspective,” he says, smiling.

“But the biggest thing is to realise that you’re on your own.”

That must be a difficult thing for a man who has spent his life in great institutions, surrounded by academics and staff and members of the public. Perhaps that explains why in the three years since he left his job he has not yet eased himself into splendid retirement. Instead, he’s taken up a directorship of the Humboldt Forum in Berlin, worked on a radio series for Radio 4 entitled Living with the Gods and now turned that radio series into a rather chunky book of the same name.

Ask him to describe a typical day now that he’s retired, and he admits there hasn’t been one yet. “It’s really only now that I’m on the threshold of: ‘What do I do?’”

That must be an even greater question when you consider what he has already done. MacGregor, after all, has been the director of not one but two of the great British cultural institutions (he ran the National Gallery in Trafalgar Square from 1987 through the 1990s until 2002, before he took over the reins in Bloomsbury), a writer and broadcaster who has helped shape the nation’s cultural conversation. His A History of the World in 100 Objects on Radio 4 was not only a huge success on its own terms but has inspired a way to approach popular history that has since been used on everything from football to the Beatles.

MacGregor’s new book Living with the Gods doesn’t take the one-to-100 route, but it is organised around objects, starting with the Lion Man of Ulm, a figure that stands around 30cm high, made from mammoth ivory some 40,000 years ago, and ending, more or less, with the Lampedusa Cross, made by Francesco Tuccio, a carpenter, out of the wreckage of a migrant boat which foundered off the coast of the Italian island in 2013. More than 300 Somali and Eritrean migrants drowned as a result.

“In a way that could hardly have been imagined sixty years ago,” MacGregor writes in the introduction to Living with the Gods, “the reassuring politics of prosperity has in many parts of the world been replaced by rhetoric and politics, often violent, of identity articulated through belief.”

This, he continues, should not surprise us, “because it is in fact a return to the previous pattern of human societies.”

It’s a point he returns to this afternoon. “One of the striking things of the last 50 years – it’s something Amrita Sen has been very clear about – is how the citizen has one identity and the others are eliminated. Because it’s useful for political purposes often.

“You can see it very clearly in elements of Indian politics. Elements of the RSS [Rashtriya Swayamsevak Sangh] and the BJP [the Bharatiya Janata Party] would assert that to be truly Indian you need to be Hindu. You can see exactly the same happening in Russia, Putin increasingly coming to the position that to be truly Russian you need to be Orthodox.”

He compares it with the British model of absorbing difference - citing the idea of a Sikh tartan. “You can be 100 per cent Sikh and 100 per cent Scottish and there is no tension between these.”

And then there’s the French model which argues that the nation comes before any faith group. Hence the issue of burkinis.

All of this was swirling around, he says, when the idea of Living with The Gods was first mooted. The result is an examination of how religious thinking has shaped us all.

The question I want to ask as a card-carrying atheist, I tell him, is if religion is a tide that is coming back in, was there a moment when it might have gone away?

“Clearly the belief was very widespread in the fifties and the sixties that as prosperity grew religion would recede and certainly in terms of politics religion would become less and less of a force,” he accepts.

But that is why we are having such problems now; why Europeans struggle so much with the very idea of faith identities. “We have lost the notion of something that is really much more widespread than you. That you find your identity in the group.”

Unless that group happens to be the nation, of course “But we know how dangerous that is,” MacGregor points out.

The thing is, he says, no matter how agnostic or atheist you may think you are, your thought patterns have been structured by the culture you grew up in and so by the religion that that culture was shaped by (in short, I may be lapsed, but dig deep enough and Presbyterianism runs through me like a stick of rock).

I’ve always thought of the Christian story – any religious story really – as a consolation myth. A way to make us feel we are not just specks of dust in the infinite space of the cosmos. MacGregor thinks that is too reductive, though.

“We need a narrative of our place in time,” MacGregor says. “A narrative that goes beyond the individual life. What is the future of our society to be and what does that demand of us now?

“I think the basis for the need of the narrative is: What is going to happen to your children and grandchildren? How are they going to survive? That’s not necessarily consoling. it’s about something else.

“That’s why the Lion man is such a good place to start, because what that’s about - as far as we can tell - is how is the society going to get through the winter. And you won’t all get through and what do you need to do so that the society will survive without you, without the individual?”

MacGregor’s own religious story is a complicated one. I tell him that I read a profile of him that described MacGregor as a “devout Christian and gay.”

“The second is certainly right,” he says. “I never quite know what people mean by ‘devout Christian’. I would define my relationship to the Christian church as that is the framework in which I ask questions. I would have great difficulty in articulating what I believe.

“I regard most of the narrative as a mythic narrative and not a historic one. But as a mythic narrative it seems to me extraordinarily compelling. Here is a narrative that encompasses suffering, idealism, the cost of moving towards the society that we want to have.

“Whatever bits you consider historically true or not seems to me very secondary. There’s a poetic truth that seems to me very enriching. I go regularly to St Martins in the Fields which is a church that exists really to explore what this means rather than assert what it is.”

It’s fair to say that religion was always part of MacGregor’s “narrative”. Growing up in Glasgow in the 1950s it would be impossible for it not to be.

When I ask him to describe the city of his childhood the first thing he says is, “totally divided religiously.”

That was apparent even to the son of doctors? Very much so, he says. “In the early fifties, mid-fifties not only did you know immediately, of course, who was Catholic, who was Protestant. But the level of social interaction was very limited.

“We were Protestants. You were very conscious of who was not Protestant. I was very conscious of which of my parents’ friends were Catholics, which is extraordinary when you think of it.

And that difference, he says, was often “hostilely articulated,” he adds.

It was still there when he was in his twenties. “I became a solicitor’s apprentice in Glasgow in 1970. I think there were six of us every year and the firm I was in had for the first time ever taken on a Catholic apprentice. 1970. Simply astonishing.

“And this was regarded as a rather radical step. The spirit of 1968 had reached Scottish law,” he adds, laughing.

Ah yes, 1968. The former director of the National Galleries of Scotland, Sir Timothy Clifford, once told me that MacGregor had been on the barricades in Paris during les evenements.

“On the barricades might be …” he begins. “I was on the street demonstrating some way behind the barricades.”

You weren’t digging up paving stones to throw at the police? “No. I was watching with amazement as it happened. I was a student in Paris at the time and to be a student in Paris at the time was to be involved.

“It’s hard to exaggerate how unpolitical student life was in the late fifties, early sixties. Partly because of the consensus of the post-war welfare state the only real political activity was around nuclear disarmament. That was it in my undergraduate days. And Vietnam. But we weren’t part of Vietnam, so it wasn’t immediate in that sense.

“To go to a country where students and student life was focused on: ‘What kind of society do we want to be? What do we want to change?’ That was very heady.”

But you weren’t a revolutionary yourself?

“Like everybody else, I got very caught up in the dynamic of the group, the movement and watching it. And realising, I suppose, it was also in a sense artificial.

“It was French students playing out a particular role that has happened in French streets over the centuries. Everyone knew what their part was. It was a choreography of protest that has a long ancestry.

“It was a sort of dramatisation of a political debate rather than an insurrection.”

Certainly, when he came back to Glasgow he wasn’t quite ready to mount a personal rebellion. Was there pressure on him to take up the law from his parents?

“There was no pressure. It could have been either medicine or law. There was no doubt that those were the two,” he says smiling.

But the more he studied the more aware he was of the limitations a career in law would impose on him. It became more and more obvious to him that it meant he was studying for a career that he could only practice in Scotland.

“I knew I wanted to be free to work somewhere else.”

Art was to be his way out. He found himself more and more interested by what images can address that words cannot, and so he ditched the law and headed to the Courtauld Institute in London, where he was mentored by Sir Anthony Blunt no less. As well as being the Queen’s art advisor, Blunt infamously was a Soviet spy (the “fourth man” in the Cambridge spy ring). The latter fact was not made public until the end of the 1970s.

For MacGregor that revelation when it came was, he admits, confounding.

“When I began studying he was the great guru in my field. He couldn’t have been more generous, more supportive. And all the feelings of admiration, affection for a teacher who helps you like that … And then discovering this other side of betrayal that had cost people’s lives.

“How do you square the two sides of the same person? That I found – I still find – very distressing, because my own experience was entirely one of generosity. And yet you know this terrible betrayal led to many, many deaths in eastern Europe after the war. I don’t know how to put those two bits together. That is just one of the mysteries of human experience.”

In 1981 MacGregor took the job of editor of the Burlington Magazine, before being appointed director of the National Gallery, beginning his career at the heart of British cultural life. Soon, he was making documentaries about art history for the BBC, including Seeing Salvation. He has always been a consummate communicator.

He stayed at the National Gallery until 2002 when he took over the job at the British Museum. At the time the museum was trying to cope with the loss of the British Library and the redevelopment of the great court, as well as dealing with a six-figure debt which saw it shedding jobs.

What was the state of the organisation that he took over then?

“What I was immediately confronted with was a very superficial problem if you like, of financial management and administration and a building project that had effectively overwhelmed the institution’s administrative and financial capacities.”

The removal of the British Library from the museum building hit the museum hard. (“The one that leaves is always in the stronger position because they’re doing new things,” MacGregor notes wryly.) And, it was also living with the decision of keeping the museum open through a major redevelopment. (“This is like having your house rewired for 20 years and going on living in it,” he says.)

“And in the public eye, of course, that was a huge story. If you look at the purpose of the institution and the scale and the nature of the institution it was a marginal problem, but a critical one that had to be addressed.”

The administrative side had broken down, MacGregor suggests. He saw his job as guiding the museum back to founding principles, to the idea that “you would try to gather the world in one building, that it would be for all curious and studious persons native and foreign. That’s all you need. What an ideal. This is the Open University for the world.

“That founding ideal was all that needed to be restated. Everything else followed from that. Because that’s what gives an institution energy.”

That is what MacGregor achieved in his time there. He was, by any measure, a successful director. (Let's not read anything into the fact that visitor numbers have fallen since he stepped down.)U

Under him the museum restated its belief in what MacGregor describes as an idea of “connected humanity, or a shared inheritance.”

That’s pure hippy, Neil, I tell him. “Well, the Enlightenment and San Francisco in 1968 are very close. You are absolutely right. It’s Woodstock.

“Broadly the eighteenth-century view is that you want to put the whole world together. Or there’s the 19th-century nationalist view that you put the national narrative together.”

“Everyone’s got to make their own choice. I’ve no doubt where I come down on that, but each is a credible defensible position.”

The Parthenon debate, you might call this. Unlike Jeremy Corbyn, he has always said the sculptures should stay in London. But not exclusively. He sees the future of the museum as enabling other museums to tell their national stories.

“You can allow other countries to tell their story in the world story and that role of the British Museum as a world lending library seems to me the logical consequence of that hippy ideal of 1753.

Of course, he is no longer a British Museum employee. I’m interested in how a man like MacGregor takes a step back? He’s 72, lives alone. As he has already said, his retirement he hasn’t started yet? Does he know what it might look like when it does arrive?

“There are a lot of novels I want to read. I’m rather looking forward to doing that.”

Living with the Gods, by Neil MacGregor, is published by Allen Lane, priced £30.

NEIL MACGREGOR ON HISTORICAL MEMORY AND THE DANGER OF FORGETTING

TEDDY JAMIESON: IN 1993 I MOVED TO THE NORTH-EAST OF ENGLAND AND WHAT STRUCK ME IMMEDIATELY WAS THE SENSE OF ABSOLUTE INCOMPREHENSION ABOUT THE TROUBLES. IT REMINDED ME THAT THE ENGLISH HAVE UTTERLY FORGOTTEN THE RELIGIOUS WARS

NEIL MACGREGOR: And that’s why they can’t understand why all this matters to people. They think it’s odd or funny or perverse or willed. They don’t understand why this is existential for most people in the world. They genuinely can’t understand because they’ve completely forgotten that.

PART OF ME RATHER LIKED THAT, THOUGH. THAT IDEA THAT QUESTIONS OF RELIGIOUS IDENTITY NO LONGER MATTER. IS THERE, THEN, A CASE FOR THE BENEFIT OF FORGETTING?

Except that … the real question with historical memory is, is it a benefit or not? What you’ve just said is the positive. You could argue that’s why the debate around Islam in Britain and particularly in England is so uncomprehending and there’s a real difficulty in seeing these are people just like us.

I’ve been very marked by my experience in Berlin. The way the Germans insist on remembering. But the point of remembering is so we now behave differently. It’s remembering to a very particular purpose.

We do a lot of commemorating here. More and more. I’m not quite sure what the purpose of it is because it’s not about behaving differently now; behaving in such a way that our soldiers will not need to go and kill people or go and be killed. The German commemoration has a very clear purpose in a changed behaviour.

There’s a very strange disjunction I think, in England particularly but maybe Britain as a whole, between the growing commemoration of the dead of the two wars; the return of November 11 in a way that wasn’t there when I was a child. And, at the same time, the almost complete amnesia about empire.

This is difficult when it comes to reviving links with the colonies because we have forgotten that history. And there’s a failure to realise that they haven’t. They certainly haven’t. I think the English amnesia, which is a very highly developed characteristic, isn’t just about the wars of religion. It’s also about the colonial wars. And the failure to understand that the other side has a very clear memory of those is problematic.