Patrick Gale is preparing to be received at New College for dinner, eating at High Table, fresh off the success of his Oxford alumni University Challenge win at Christmas, when we speak.

Surprisingly, he is “rather nervous” at the prospect, feeling himself unworthy of the invite — a “mere lighweight novelist”, compared to his more academic dinner companions. And yet how many intellectuals can boast his book sales, advances, fan-base, or indeed lifestyle? Not only is he an acclaimed and very popular novelist, but Patrick Gale is also a fascinating man. His father was a prison governor, and so young Patrick lived with his parents and three older siblings in various prisons around England. Patrick can even recall the time Ronnie Biggs did a bunk from Wandsworth Prison while his dad was in charge.

After a solid schooling at Winchester — The Pilgrim’s School, followed by Winchester College — where Patrick sang with the renowned choir and developed his musical side, he read English at New College, became a novelist, moved to Cornwall and got married to Aidan Hicks, with whom he runs a farm near Land’s End, and where Patrick writes overlooking the sea. As if his life wasn’t full enough, he also plays the cello extremely well and sings like an angel. That he is appearing at the Bloxham Festival of Faith and Literature is a complete coup for the organisers, not only because Patrick calls himself a “woolly Anglican”, but also since he has “a writing year then a talking year, and this is a writing year”.

So what tempted him away from his keyboard? “[The religious theme] is a nice idea for a literary festival, because all the others are so general, and it’s wonderfully unfashionable.”

The novel the writer is being distracted from traces his great-grandfather’s life and attempts to unravel the secrets that led to his banishment to Canada, leaving his wife and daughter behind.

“l assume it was probably because he was gay, but I inherited all his letters and am hoping to find some clues because occasionally he wrote to my mother. We had a dressing-up box which had these bear skin gloves from North America which we knew were from Cowboy Grandpa, but apart from that we knew nothing about him. So maybe it’ll be a bit like Brokeback Mountain,” Patrick says, roaring with laughter.

“So I’m off to Canada later in the year. I’ve rented a log cabin as close to where he lived as possible, which is now a ghost town, but all the houses are still there. I might have a whole other family who knows? Because he was the black sheep from my mother’s side, while my father’s were all virtuous landowners and judges.”

Not that his father’s side was any less fascinating. Anyone reading Rough Music, set in a prison and seen through eyes of the governor’s son, will have noticed the parallels between his and Patrick’s life, “although it wasn’t until my 40s that I realised I could stop making things up and start pillaging from my own life,” he accedes.

Neither does Patrick see his prison upbringing as unusual. “We always had massive houses and gardens, often too big to furnish, and the prisoners helped out in the gardens. It wasn’t weird to us, it was normal and I was a happy teenager.

“We met the prisoners all the time – my mother was a governor’s daughter and we saw nothing to be frightened of. It was occasionally amusing when we’d come back from school with a note saying we were using filthy language yet had no idea what it meant. As for what they’d done, there was an etiquette that you didn’t ask. “The only downside was we had to move every five years – irritating when you want to make friends. But it was worse when my father retired and we had to live without guards – we felt vulnerable then.”

But if Winchester encouraged Patrick’s artistic side, it was Oxford which taught him about research, study and how to organise ideas. “I was a real swat, turning up at New College having read the entire reading list which I didn’t realise was voluntary. When else do you get the chance to read all those big 19th-century novels?”

Did he enjoy his time here? I wanted to go to drama school but my father wasn’t having it. He was seriously academic and also an Oxford man. But yes, Oxford got under my skin in the way that university does.” In a good way or bad, I ask? “Well you are so vulnerable and changing at that age, so in a good way, but I never got away from the feeling that I could have done better, which makes me feel guilty.”

Needing to get the acting bug out of his system, Patrick wrote his first novel “for fun” while working as a singing waiter, which unbeknownst to him a friend sent off to a literary agent who offered just enough money to write seriously and pay the bills. “Looking back on my early novels I’m amazed they were published and I certainly learnt my craft in public. But until then I had no idea I was going to become a novelist,” he remembers.

Debunking to Cornwall aged 25, Patrick has lived there happily ever since, producing 16 novels to date, living on his husband’s farm, “which has been in his family since William The Conqueror. I’m in the outbuilding, which used to be a bull shed.”

Perfect for a writer then? “Well writing is so nebulous you need to protect your work and shut yourself away. But I also love all displacement activities like cooking and gardening,” he laughs.

And then Patrick switches to talking about the festival, no doubt because he needs to get back to work, and about being interviewed by Sally Welch about faith in fiction. So where does he stand on religion? “I’m not falsely pious but find the subject quite stimulating. I had a very Anglican childhood but I don’t really know what I think, which proves helpful when writing. So my books are quite pick and mix.

“But I’m drawn to writing about music and faith, because they are are difficult to put into words – half the buzz is still the ventriloquism, inhabiting other people, but it’s also about having an open mind.” New College should take notes.