It’s hard to think of a British politician held in greater affection in Ireland than Chris Patten, and difficult to imagine a more unlikely profile for an Irish hero. A member of the House of Lords since 2005, Patten is a former Conservative party chairman and government minister who has been at the heart of the British establishment for most of his adult life.

After he lost his seat in Bath in 1992, Patten began his very own march through the institutions, national and international, starting in Hong Kong where he was the last British governor before the colony was handed over to China.

Since then, he has served as a European Commissioner, chairman of the BBC, chancellor of Oxford University and an adviser to the Vatican on media strategy, becoming known as the “Grand Poobah”.

In Ireland, however, he is best known and most admired for his role in 1999 as chairman of the commission which transformed the Royal Ulster Constabulary (RUC) into the Police Service of Northern Ireland (PSNI). The commission made 175 recommendations, including a new oath for officers, removing the British flag from police buildings and recruiting equal numbers from both communities.

I think it’s fair to say that my time in Northern Ireland . . . made me much more aware of my Irish roots

“I think it’s fair to say that my time in Northern Ireland, both as a junior minister, which I really greatly enjoyed, and then going back to do the police commission, which was the most difficult job I’ve ever had, made me much more aware of my Irish roots,” he said when we met at his house in south London this week.

Irish Catholic

Now 73, with several heart attacks and some serious cardiac surgery behind him, Patten is physically slower than when we knew each other in Brussels over a decade ago. But he has lost none of the intellectual vitality, fluency and mischief which made him such an attractive politician.

Patten grew up in an Irish Catholic family in west London, the son of a charming but mostly unsuccessful music publisher whose forbears had come to England from Co Roscommon.

Chris Patten on Brexit: “I’m not bloody well going to get over it. I think that it’s the worst thing politically that’s happened to Britain in my political lifetime.” Photograph: David Levenson/Bloomberg

In his new book First Confession, which he describes as “a sort of memoir”, Patten explores his Irish roots and his growing awareness of the Irish part of his identity.

“As I thought more about where I came from, it was the Irish dimension which particularly struck me. And I thought to myself over and again, first of all, this is a fairly typical European diaspora story,” he says.

“I became more aware of my Irish roots and thought a lot about them and realised it wasn’t just that I was a scholarship boy, I was part of a diaspora story which could have happened on so many continents.”

Patten won a scholarship to St Benedict’s, a fee-paying Catholic school and later an exhibition to Balliol College, Oxford, where he read modern history. After a brief stint in the United States, where he worked for the liberal Republican John Lindsay, Patten returned to Britain and joined the Conservative Research Department in 1966.

He rose fast as a party apparatchik and was already a significant figure within the party when he entered parliament in 1979, when Margaret Thatcher became prime minister. Patten worked closely with Thatcher and writes about her more approvingly than about her predecessor, Ted Heath.

There’s a sense that being in No 10 can drive people into abnormality

“I think that there’s a sense that being in No 10 can drive people into abnormality. You notice the difference between somebody as leader of the opposition and becoming prime minister. As leader of the opposition, you may get what you want when you express a view on getting up in the morning, or you may not. When you’re prime minister you say something and the windows up and down Whitehall rattle. And I think that has a bad effect on some people. I think they usually have difficulty in getting advice if it involves being told things they don’t want to hear,” he says.

“Major was the cleverest prime minister I worked for. It sometimes surprises people when I say that because Heath and Thatcher had gone to Oxford. They were both classic lower-or-middle-class scholarship products. I think Major left school when he was 16. He was very much self-taught but very clever, a wonderful negotiator, terrific at knowing people’s body language, always had complete control of the brief, thoroughly decent.”

Brexit worse than Suez

As one of his party’s most ardent advocates of Britain’s membership of the EU, Patten is horrified by Brexit, which he describes as a doomed attempt to pacify the right wing of the Conservative Party. Contemptuous of what he describes as “all this ideological crap about sovereignty and taking back control”, he nonetheless believes that Britain will leave the EU in 2019.

I’m not bloody well going to get over it. I think that it’s the worst thing politically that’s happened to Britain in my political lifetime

“I think it’s difficult to see how it’s avoided in any rational way. Obviously there are two things I would feel. The first is that when I’m told that people like me have to get over it, I’m not bloody well going to get over it. I think that it’s the worst thing politically that’s happened to Britain in my political lifetime. It’s worse than Suez in a lot of ways because Suez was clearly the end of a story. Joining the European Union was part of our effort to actually find a different role for ourselves in the world,” he says.

“How can you actually snuff out all of the opportunities which Europe offers in the name of this chimera of sovereignty? I think that the longer things go on, the more it will become apparent that the costs are very real.”

Europe has destroyed the last three Conservative prime ministers – Thatcher, Major and David Cameron – and divisions in the party over Brexit have left Theresa May all but paralysed after last month’s disastrous election. Patten expects that, despite her weakness, May will remain in Downing Street for another couple of years, perhaps until the Brexit negotiations are complete.

“She’s there because she’s there because she’s there because she’s there. She’s not a bad woman. She’s not, I think, particularly ideological,” he says.

“If it’s not Mrs May, who is it to be? I think it’s very difficult to see how you move seamlessly to some other Conservative leader who will be able to play the hand better.”

Patten was shocked by last month’s election result for his party, particularly the loss of voters under 45 to Jeremy Corbyn’s Labour Party. He is contemptuous of Corbyn, and outraged by attempts to compare him with the late Labour leader Michael Foot.

“I mean, Michael Foot was a brilliant essayist, a very good historian, a fantastic speaker. To compare Corbyn with that is like comparing the admirable Ed Balls of Strictly with Nureyev. This not like with like,” he says.

Catholicism

Patten’s Catholicism is important to him, culturally as well as philosophically, and he has remained observant throughout his life. In 2014, one of Pope Francis’s top advisers, Cardinal George Pell (now under investigation in Australia for alleged sexual abuse), asked Patten to oversee a reorganisation of the Vatican’s media operation.

Patten was pleased to do so, partly because Francis’s brand of Catholicism is similar to his own – liberal but pragmatic and committed to strengthening the church as an institution. Like many liberal Catholics, Patten would like the church to talk more about social justice and less about sexual morality. But he stops short of urging any change in the doctrines that classify remarried or gay Catholics as sinful.

“I think you can redo the rules at the risk of splitting bits of the Church off or you can underline the importance of the Church being pastoral, which I think is a more sensible approach, and allow things to change and emerge.

“I remember going to my grandson’s First Communion. It was a lovely occasion. But just wondering as I looked around the church, how many grown-ups there go to Confession. They’re not bad because they don’t, it’s just that it’s not like it was in my day, or when I was younger,” he says.

Last governor: Chris Patten receives the Union Jack after it was lowered over Hong Kong for the final time, on June 30th, 1997. Photograph: Emmanuel Dunand/AFP/Getty

As Patten looks around the world, at Brexit, the election of Donald Trump and the West’s timidity in the face of autocrats from China to Saudi Arabia, there is little to encourage him. At home, he is repelled by the rise of English nationalism, which he condemns as “profoundly un-English” in its sentimentalising of history and glamorising of English institutions.

Despite the gloomy global picture, he suggests that it would be “a sort of demented egocentricity” to imagine that the kind of politics he believes in no longer exists.

“I think a belief in a role of the state in promoting a welfare democracy without snuffing out individual enterprise; I think a belief in international co-operation; I think a scepticism about demolishing institutions; I think an understanding of the relationship between strong institutions and solidarity; I think a belief [which doesn’t necessarily mean religious] in a society having a moral core; I think a belief in avoiding a sort of bread and circuses decadence resulting in a lack of any sense of honour in foreign policy – I think all those things still exist,” he says.

“They may just not be winning the game at the moment.”

First Confession: A Sort of Memoir is published by Allen Lane