When her 2005 novel Labyrinth became an international bestseller, Kate Mosse was transformed from being a published author to a pubishing phenomenon.

“I know how EL James feels, in a small way,” she laughs. “You don’t expect it. I had been a publisher for many years. I had published four books beforehand. I was in my mid-forties and pretty settled. Nobody expects it to happen to them.”
Labyrinth, a ‘time slip’ novel set in 1209 and 2005, was the first in a fantasy trilogy inspired by the history of Carcassone in the Languedoc region of southern France.
“It was chosen for the Richard & Judy book club. It was on the television and I sat in our sitting room, on the floor, at 5 o’clock in the afternoon, very naughty with a glass of wine, because I was so nervous. You don’t get to see them film, you don’t know if they’re going to like your book, you just know you’re going to be on the television. Of course, they could, and sometimes did, say they didn’t like a book, so it was really nerve-wracking. You’re being live reviewed but you’re not there to defend yourself.
“They were really lovely – and it subsequently went to number one and stayed there for six months. Suddenly it was the book everyone had in their hands. The good thing about this happening to you when you are middle-aged is you know it’s luck – your book is in the right place at the right time.”
Citadel, the final installment, this time set between 342AD and the early ‘40s, has just been released.
“It feels really sad. Although you can read them as separate books, each time I was writing I felt I had a bit more story to tell about that part of France, about its history. But when I was writing this, I knew it was the end. For 23 years we have lived on and off in Carcassone. When we first went there I was pregnant and now the children are grown and have left home. It feels like a whole period of time has come to the end at the same moment. It’s sad, but also quite liberating. I’ve mixed feelings.
“The books are love songs to Carcassone,” she adds. “I learnt how to be a novelist because of Carcassone. They were inspired entirely by its landscape and history. I wanted to know everything and when I started to do research, characters kept coming into my mind. It was place, landscape and history – and out of that came genuine passion.”
Citadel tells the story of female members of the French Resistance during World War II. This is contrasted with another period of warfare in the region in the fourth century. During both periods, a mysterious heretical text known as the Codex plays an important part.
“I was really interested in the parallels between fourth century Gaul and the 20th. In both periods of time, the Empire was falling apart. There was resistance to occupation and everybody lived with the knowledge that at any moment, everything could fall apart. In the fourth century, as Christianity started to take hold, there was a battle between the orthodox lobby and the more mystical lobby and there were mass burnings of religious texts. In the ’40s there were mass burnings of books.”
Although Citadel is a fantasy novel, it’s also based on the history of the region. However, Mosse notes, it’s perhaps not the best choice for a history purist.
“The thing is, I’m not writing about the Second World War, I’m writing about female Resistance members, about Sandrine, Marianne and Lucie and their imagined stories. My books are a mixture of mystical and real history. I’m sure history purists won’t like the fantasy elements in my book, but they probably don’t like fantasy anyway!”
A monument to the Resistance in Carcassone inspired the story.
“The novel is dedicated to two women who died in the Resistance, who have never been identified. Women’s history in the Resistance has been very much underwritten compared to the male Resistance story. In Carcassone, men and women worked alongside each other, we know this to be the case. One of the reasons women’s stories are so underplayed is that, when it was over, many women did not want to think about it. They did not want to be heroines or given medals – they were fighting for the right to live quiet lives so they went back into the shadows.”
If women’s stories have been written out of the history of the French Resistance, much like the way women’s contribution to the 1916 Rising has been glossed over, and in some cases literally airbrushed out of photographs, in contemporary culture, women’s artistic achievements are often overlooked. This is one reason why Mosse is one of the forces behind the Women’s Prize for Fiction (formerly the Orange Prize) – a literary award that has attracted both praise and censure in equal measure.
“I find it really depressing that the idea of celebrating women is seen as a frightening thing or a sexist thing. There are as many men who support the prize, as there are women who don’t. We celebrate men’s achievements all the time, and rightly so. I watch a lot of sport and I don’t think, ‘Why are there only men on the team?’ I think, ‘Score a goal for God’s sake!’ The crowd watching is men and women and we celebrate men’s achievements every weekend. Nobody says that’s sexist. This is the same. The prize is about saying to men and women readers that these are brilliant books.”

Citadel is out now, published by Orion.