One of David Trimble's students was interned in the early 1970s because of his involvement in a republican club. Every week Trimble, an Orangeman and a member of the hardline anti-republican Ulster Vanguard movement, went up to the Maze to give him a tutorial.

That story came from the ex-student, not from Trimble, who would never tell a story to his own credit unless it concerned some obscure intellectual victory. His greatest regret when he became leader of the Ulster Unionist Party was that he would no longer have time to sit on select committees going through bills line by line: he was immensely proud of the contribution he made to improving an elaborate Criminal Justice Bill.

Trimble's main relaxation is music: opera, classical and Elvis Presley. "I feel a soft spot for Trimble," said a BBC producer to me the other day. "I saw him at a concert by himself in the Wigmore Hall at six one evening, and thought how unusually civilised for a politician."

It is not surprising that he was alone. Trimble is very shy and, as he says himself, terrible at small talk, so most people who meet him gain no inkling that he loves art, music and books. In 1990, shortly after he became an MP, I took him to lunch at the London Academy Club. "Who runs it?" he asked. "Auberon Waugh," I said. He sighed. "Since I became an MP I've had to cancel my subscription to Waugh's Literary Review. No time."

He is an inveterate book-buyer, history and politics dominate his reading: biographies, analyses of the Middle East, explorations of intellectual or economic ideas.

Anthony Trollope is his favourite novelist. And in poetry, not surprisingly for an Ulsterman, Kipling leads the rest.

Trimble's social awkwardness is compounded by insensitivity and an almost total absence of tact. Ask him a question and he'll give you a straight answer without any thought of the consequences. I told his wife, Daphne, a story of how at an Anglo-Irish conference a couple of years ago he managed innocently to alienate everyone around us by responding to a question with brutal honesty. "That's David," she said. "Barge in feet first". When I remonstrated with him on that occasion, he just shrugged and said: "I answered the question she asked. What do you expect me to do?"

Daphne, though as easy socially as Trimble is difficult, is from the same tradition of directness. She will talk with absolute frankness about Trimble's failings as a communicator and his impatience with what he perceives as stupidity. "But he's getting better," she said the other day. "Mind you, he could hardly fail to."

He is getting better at relaxing, too. The three-week holiday in Europe that they take with their four children (Richard 16, Victoria 14, Nicholas 11 and Sarah 6) every summer used to be spent remorselessly charging from art gallery to church to art gallery with music in the evenings, but now he has learned to take days off and laze around and enjoy good food and a bottle of wine.

Daphne was an ex-student of his whom he married in 1978. She continued to practise as a solicitor until his political career made it impossible: these days she works half-time in his constituency office. Having assumed that like every Presbyterian home I've ever visited, chez Trimble would be a model of neatness and cleanliness, I was relieved to hear that there are piles of papers everywhere, that Victoria's room is lined with posters of Boyzone and that Daphne hadn't had time to Hoover for weeks.

Like David, Daphne is fatalistic about his career. If his party turns against him and he ceases to be leader, so be it. "He could get a life." The children wouldn't mind either. Richard, who takes after his father in being highly academic, knows that the one thing he never wants to be is an MP.

Daphne, like David, has a sense of humour that carries her through the worst days. Trimble's ability to laugh at himself is one of his most endearing characteristics. Interviewing him a few months after Drumcree 1995, I asked about the repercussions on his career of his notorious cavort with Paisley through the Orangemen's ranks, a happening born of relief and happiness after days of strain.

"A lot of people were really upset about it. Not everybody was as humorous about it as you were." And he laughed merrily, which was pretty impressive considering what I'd written in a London newspaper at the time was that he and Paisley had looked like the principals in a gay wedding.

But Trimble does not easily take offence. In the 13 years I've known him, I've criticised him freely and it has never bothered him. He recently reminded me that the first time we had a conversation, late over beer at an academic conference, I told him that his trouble was that clearly he was normally three pints under par.

The often pedantic, academic lawyer cohabits in Trimble with a romantic with an adventurous streak. As a youth, he joined the Air Training Corps and flew a glider. Later, a member of the Orange Order and Vanguard, he became involved in non-violent street protests and enjoyed what a university colleague once described as "prancing around the streets"; he is quite proud of his two minor convictions for offences related to illegal parades.

Although Trimble is anti-sectarian and is succeeding in bringing Catholics into the UUP, he is implacable in defence of his own people. At Drumcree 1995, when the Orangemen came out of church to find their legal parade blocked by republican protesters, convinced that capitulation would be disastrous for the morale of the Protestant community, Trimble was as determined as anyone to sit it out.

Early in the stand-off, he said to the local worshipful master: "If this goes badly, you and I have to be the last two people to leave." I saw him at Drumcree the next year where, contrary to popular mythology, he made an enormous contribution to keeping the peace, and he reminded me of an army officer controlling unruly troops. He sought a compromise, but he was never going to countenance giving in. If he thinks he is in the right, "No surrender" will be the order of the day.

One of Trimble's greatest assets these days is his ability to cope with unpopularity. His social inadequacies have always been misread as arrogance and rudeness; fellow academics shunned him because of his extracurricular activities; he is too much of an intellectual for most of his party; most of his parliamentary colleagues have never forgiven him for his surprise win; he has been vilified all around the world over Drumcree as a triumphalist bigot; a scurrilous book about to be published in the US alleges his collusion in loyalist murders; he is routinely denounced by Robert McCartney and Ian Paisley as a traitor; and, for a change, his life is now threatened by loyalist rather than by republican terrorists.

Whatever he is, he is no push-over.

Ruth Dudley Edwards is a historian and commentator on Anglo-Irish affairs