The Essex Serpent author Sarah Perry talks challenging stereotypes and the real way to think about Victorian England

It’s unusual for a historical page-turner to attract such praise, but Perry breaks with many conventions. Cora Seaborne, her novel’s protagonist, is the antithesis of a stereotypical Victorian widow. Tall and far from slender, she often dresses in masculine clothes.

And yet everyone falls in love with her. “I’ve had emails from people thanking me for writing a heroine who is fabulously attractive, but not a delicate, fairy creature,” she says.

Some of Cora came out of Perry’s own experience growing up, struggling to identify with women in fiction. “I’ve always been quite tall and stout myself and in the books I read the heroine would always have flaxen hair and a tiny waist. I remember thinking: ‘Does that mean I won’t get to be a heroine?’

“Cora was based on Victorian images of beauty. If you look at the great music hall actresses who were the pin-ups of the time, they were really bosomy creatures with great big handsome faces and strong chins.”

Perry, 38, certainly had an unusual childhood. Born in Chelmsford, into a strict Baptist family, the youngest of five daughters, she grew up in a home without TV or pop music. The King James Bible was read at mealtimes and she devoured 19th-century novels and paintings by the Pre-Raphaelites.

Today she describes herself as “post-religious” (she left the Church over its stance on gay marriage), but “it has profoundly affected everything about the way I write. I have a tendency to write in iambic pentameter, which you find in the King James Bible.”

Perry studied for a PhD in London, where her supervisor was former poet laureate Andrew Motion. Her first novel, 2014’s After Me Comes the Flood (set in Norfolk, where she now lives), was longlisted for The Guardian First Book Award.

Then one day, out for a drive with her husband, he spotted a sign for the Essex village of Henham and told her about the legend of a serpent there. By the end of the journey, Perry had plotted her entire second novel. The Essex Serpent is set in 1893. Young widow Cora, an enthusiastic amateur naturalist, moves to the wetlands of Essex, where a sea serpent is terrorising villagers. In many ways the serpent is a symbol of discord – from awakening sexuality to the knowledge of good and evil. Perry says some fans have identified it as a symbol of post-Brexit anxiety.

We see the fight between superstition and faith. But this is also a world where campaigners are fighting to clear the slums and provide lighting and sanitation. Perry wanted to “challenge the dusty, repressed, slightly theme park image of the Victorian age”. Not only was it an age of liberal free thinkers – in the novel, Cora’s great ally, vicar Will Ransome, reads Charles Darwin – it was also an extraordinary moment for women’s suffrage.

“We need a little bit of a corrective to the view of Victorian England as a fog-shrouded, choleraridden place of poverty,” she argues. “Because this was the time that Joseph Bazalgette laid the sewers that still look after London, the hospitals were built that we still use. People don’t realise that women have had the vote far longer than 1918. There are records of women voting in local elections.

“Trades unions were up and running. The match girls at Bryant and May [who went on strike in the East End of London in 1888] helped bring about changes in the labour laws. So it was a time when the modern age really began.”

Those are not the only shades of the modern world in the novel. In one gripping scene, Cora’s friend, surgeon Luke Garrett, performs pioneering heart surgery. By way of research, Perry watched videos of open-heart surgery on YouTube.

Then there’s Cora’s son, who would be on the autistic spectrum today, but Perry prefers to think of as a free spirit: “I wanted to challenge this idea of normal and abnormal behaviour.” The novel also “reverses the preconceived idea of Essex” – the landscape shimmers with wonder and danger. “I’m Essex born and bred and if I close my eyes now, I can summon up that landscape that’s in my blood.”

Last year – after a long period of deteriorating health – Perry was diagnosed with Graves’ disease, an autoimmune disorder that has affected her heart, caused joint pain and problems with her eyes. She spent 40 per cent of the year in bed. Thankfully, she is now writing again – her third novel will take in Gothic horror and Prague.

One of the things Perry is most thrilled by is her large male readership. “It really gives the lie to the idea that men will not read women’s fiction,” she says.

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