Fiona Mountain was torn between two paths in life, but both involved long-haired men in tight trousers.

Having worked for the likes of John Peel and Steve Wright as a press officer at the BBC Radio One in the 1990s, hanging out with rockers such as Bon Jovi and Guns ’n’ Roses, she is now going hell for leather in pursuit of success as a writer of historical fiction.

She has spent the last two years working on her new book Cavalier Queen, set in the English Civil War.

It tells the true story of Charles I’s French wife Henrietta Maria and her chamberlain and confidante, Henry Jermyn, Earl of St Albans, after whom Jermyn Street in London is named.

While her years at large with the Radio One’s summer roadshow might suggest she will not be offering her readers any new interpretation of puritanism in the 17th Century, Ms Mountain’s book certainly provides a new take on the marriage of Charles and Henrietta, who spent much of the English Civil War together – though based at different colleges – in Oxford.

Asked at a literary festival about what had attracted her to the 17th Century she said: “I could have said that it was a period of turmoil and violent political change. But instead I admitted I like men with long curly hair, lacy sleeves, thigh high boots and skin tight breeches. I mean, what’s there not to like.”

But for all her self-deprecating humour, it is clear that Ms Mountain, who lives in the West Oxfordshire village of Kingham, has immersed herself in the story of Henrietta Maria and the court of Charles I.

Ms Mountain, 40, said: “Henrietta’s love for the Charles I is one of the most famous love stories in history. But there were contemporary rumours that she and Henry were lovers.”

She was 100 pages into her book, after eight months of research, when she read Anthony Adolph’s biography of Henry Jermyn.

She added: “It led me to abandon what I had written completely. I realised I was writing the wrong story. I needed to tell the story of Henrietta and Jermyn. I just could not believe that it had not been told before.”

She now strongly believes that the pair were indeed lovers. “They were so close together over so many years. She was pretty and vivacious and they were alone together for years.”

Following Charles I’s execution he was to live with her at her chateau at Colombe in France. “He never married. When she died he said, ‘I have no tears left to cry. Love has cost me too much’.”

Ms Mountain, a mother of four, who is separated from husband Tim Mountain the composer, addressed the love story of Bounty mutineer Fletcher Christian and his cousin Isabella Curwen in her first book, Isabella, which was shortlisted for the Romantic Novel of the Year Award in 2000.

At school in Sheffield she admits to having been obsessed with a varied assortment of characters from history including aviator Amy Johnson and Prince Rupert.

But she was not to go to university. Instead she headed to London to pursue her other great obsession music. “I always wanted to work for Radio One. The reason was I had this massive crush on David Essex.”

“I wanted to be Kate Bush but the next best thing was going to work in the music business.”

She was to handle the PR for all the station’s DJs on Radio One. Working for Peel was the highlight. “He was adorable; not in the least egotistical, just in it for the music. He had massive respect across the music industry. People thought he was God.”

But the golden age of Radio One was ending before her very eyes amid bitterness and bitching to almost rival anything that occurred in the Royalist court at Oxford. “It just had to happen,” she now says, reflecting on the axing of many of the DJ legends.

So Ms Mountain decided the time had come to keep another promise to herself to write a novel.

When she next returned to Broadcasting House, it was to be interviewed herself. Everything and nothing had changed.

She was a best-selling author, but still wearing a leather jacket and studs, and more than ready to gossip about men with long, curly hair.