The cackling witch on a broomstick is a benign figure for kids dressing up at Halloween. But 400 years ago, witchcraft was a terrifying collective fear, for both the people who believed themselves cursed and the often innocent women executed for it.

In her book Witches: A Tale of Sorcery, Scandal and Seduction, historian Tracy Borman estimates 100,000 people were tried for wtichcraft between 1450 and 1750 in Europe.

“Kids dress up at Halloween and it’s all quite jolly but that’s totally turned on its head from when it was the number one evil in society.

“What fascinated me is I always thought the stereotypical image of the broomstick and hat was a modern Hollywood invention but it was totally authentic. I saw a 14th century engraving and she looks just like that.”

The English taste for the occult had diminished until James I took the throne in 1603.

Introduced to the subject during a stay at Elsinore castle, he later wrote the book Daemonologie in which he sanctioned the practice of witch-hunting.

“Unable to get back to Scotland from Denmark, he became convinced he couldn’t sail because his fleet had been bewitched, and became a crusader against witchcraft.

“Suddenly everyone’s trying to flatter the king’s obsession and it spawns a literary flurry of witches and devils like Shakespeare’s Macbeth.”

That was bad news for the elderly, misfits and women practising traditional medicine in small villages.

In an age where harvest failures, mysterious diseases and sudden death were frightening and unexplained, it was easy to believe that “evil was at work”.

“It was a very insular society. If anyone didn’t fit in or were poor or stood out, it was a handy way of scapegoating someone, or settling petty local squabbles.”

“Women were already second-class citizens, chattels owned by husbands and fathers, and single women were the lowest of the low.

“Anyone could be accused, for arguing with your neighbour, not attending church, the sickness of someone’s pig. Once accused, your life wouldn’t be worth living. There was vigilante justice and violence.”

Although up to 50 per cent were acquitted, for those on trial, the average court case lasted 20 minutes.

Confessions were common, many wrought after sleep deprivation or torture when jailors would put words in their mouth.

“It was believed that when a witch made her pact with the devil, he would leave a mole or teat – witch pricking used a dagger to stab every mark on their body testing for the devil’s mark which supposedly wasn’t painful to the touch.”

This might involve stripping the witch and stabbing the genital area.

“There was clearly a sexual nature to it. In a quite buttoned-up society, it gave licence to express certain desires, the witchcraft pamplets were like the porn of the day, giving intimate detail of the witch’s examination.”

Another test involved throwing the accused into a cess pool; if she floated she was guilty, if innocent she drowned.

Borman highlights the 1618 case of widow Joan Flowers and her two daughters Margaret and Philippa. It was unusual in involving a member of the aristocracy, their previous employer the Earl of Rutland.

“They’d enjoyed an unusual amount of favour but other servants hated them and hounded them out with suspicions and rumour.”

When one of the Earl’s sons died in convulsions and the other fell sick, the women were accused of cursing them.

“The Earl was one of the most distinguished men at James’ court, and his two sons bewitched to death was the equivalent of today’s headline news.

“The Earl resisted bringing charges for a long time and only when medical cures failed did he make accusations, in desperation while his second son was still alive, thinking if you accused a witch the victim would be cured.”

Hanging

Joan died en route to prison, her two daughters were hanged at Lincoln and once the second son died, the Earl’s daughter Katherine married King James’ favourite the machiavellian Duke of Buckingham who inherited the estate.

As joint chief curator of the Royal Palaces, Borman’s office is at Hampton Court which is handy for her next book – a biography of Henry VIII’s chief minister Thomas Cromwell: “I am very lucky. It’s a real historian’s job being a curator for the palaces – I get up close to fascinating artefacts – it feels like you have your hands on history.”

And her favourite artefact: “It doesn’t sound interesting but the elaborately decorated glazed green ceramic flute used to pump steam into Henry VIII’s Turkish bathroom at Westminster Palace is astonishing.

“Cromwell is the first man I’ve ever written about but what a man to start with!”

n Tracy Borman talks about her book at the LJCC, Ivy House, North End Road, NW11. Booking at www.ljcc.org.co.uk or 020 8457 5000.