Orphanage boy who shaped our leaders

After all, he had written to the parents of another boy, describing him as "a great thickhead." And then there was the one he described as "about as lively as an inanimate centenarian," and who he likened him to "a sheeted tombstone."

You hate to think what Michael Kidson would have said about the pupils he didn't like.

Yet for all his waspish comments, Eton history master Michael Kidson was remembered by huge affection by most of his pupils, including the former prime minister who wrote him a note thanking him for the impact he had on his life. And the life of the legendary teacher, who rose from humble beginnings in Shropshire and Wolverhampton, is now celebrated in a new book by former pupil Jamie Blackett.

Kidson, who died two years ago, aged 85, had a difficult upbringing. His parents separated when Michael was a baby – after spending a short time in South Africa, his father served time in prison before dying when Michael was still a small boy. What happened to his mother is also unclear, but she also walked out on her young son and was never heard of again.

It fell to his paternal grandfather, a retired vicar, to bring up young Michael in Church Stretton, and it is thought that he also lived for a short while with his stepmother in the Ludlow area. But when Kidson's grandmother died in 1941, his grandfather ­– by this time in his mid-80s – felt he was no longer able to manage.

Michael, now aged 12, was sent to the Royal Orphanage of Wolverhampton, now the Royal Wolverhampton School, and remained there until he was called up for National Service. He signed up with the King's Shropshire Light Infantry, at Copthorne Barracks before going on to read economics and history at Gonville and Caius College, Cambridge. After briefly working for Shell as a graduate trainee, he found his true vocation in teaching, and arrived at Eton in 1965.

His early life would have a profound impact on his career.

"From his bleak childhood grew a man who did not care to see unhappy children," said Mr Blackett.

And for all the terror he could strike into unruly youngsters, his lessons were nothing if not entertaining, and his explanation of political history would captivate a young David Cameron.

"He was so passionate about Gladstone, that when he read the last few pages of Magnus’s great biography aloud in class he started to cry," recalled the former prime minister at his former teacher's funeral.

“He had a large block of wood on his desk which he would throw at the head of any boy not concentrating. He would put you on detention, but only for reasons that were completely outside the rules – being boring or smelling. We were all devoted to him.”

It is hard to imagine many teachers getting away with such maverick behaviour today, but the fact that Kidson is held in such high esteem by his former pupils despite – or perhaps because of these excesses – is testament to the way he managed to capture their imagination and get the best out of them.

Half a croquet ball was another weapon he would use against children who looked like their minds might be elsewhere.

Mr Blackett recalls how one day in 1976, the year before he started at Eton, a class hid his ball in an attempt to prevent such attacks.

"In its place Kidson reached for the nearest object, an electronic calculator belonging to a wealthy boy in the front row," he said.

"It exploded into a thousand pieces as it hit the rear wall. All protestations by its owner were met with characteristic indifference. The pupils later returned the croquet ball to prevent further losses."

The Archbishop of Canterbury is another former pupil who found himself on the receiving end of Kidson's wrath when he made a spelling mistake.

"I was yelled at for not spelling 'particularly' properly," recalls the Most Reverend Justin Welby. Another boy was forbidden from using the word "hopefully".

"It makes you sound like a football manager," the teacher told him.

Another pupil was described as a "truculent navvy", while the parents of a boy named Guy Butterwick received a letter announcing that "your son has passed his A-levels. An extraordinary achievement for a great thickhead like Guy."

A true eccentric, Kidson would bring his pet spaniel into class, and would mischievously get their names wrong, particularly if they were foreign.

Mr Cameron recalls two German exchange pupils, who got the full Kidson treatment.

"They were called Bommel and Hoffman but they became Rommel and Hoffmeister,'" he says.

"He would treat them with a Fawlty-like courtesy, saying: 'I am very fond of your country and I have visited it many times . . . after the war, of course'."

Blackett himself remembers being described by his old teacher as "a fairly indolent fellow", but says he was never offended by the barbed comments.

"We boys respected Kidson for speaking his mind, knowing it was all part of his unstinting drive to get the best out of us," he says.

Mr Cameron, who during his time as prime minister invited his former teacher to stay with him at Chequers, also remembers Kidson being a stickler for spelling, punctuation and grammar.

"He once made me write out 100 times: 'I will always use a comma after the adverbial however'," the former PM recalls.

And when in his later years Kidson was asked how he remembered the young David Cameron, his old master took great delight in describing him as "a totally unremarkable boy", adding that the A-grade he achieved in history A-level was "among the most inexplicable events in modern history".

The future premier clearly bore his teach er no hard feelings though. As was the custom at Eton, on leaving school he gave his teacher a photograph, and wrote on it: "'I know you think that I know less history than your dog, but all the same I greatly enjoyed being taught by you.

"As you once said, I fear the Oxbridge dons may well be more perceptive than the A-level markers, but the strangest things can always happen.

"Thank you once again for everything, love David."

There was a softer side to the teacher, as one pupil discovered when he sneaked out at night to watch the racing at Windsor, a transgression which was punishable by beating. Kidson was also attending the races, and feared the worst when he bumped into his master.

He needn't have worried.

"I believe I teach your twin brother history," Kidson remarked sardonically, then held his binoculars to his eyes to watch the race. The incident was never mentioned again.

And although Kidson was publicly dismissive of his protege, old Etonian Nicky Dunne says that he was intensely proud of teaching somebody who went on to hold the highest political office in the land.

Dunne recalls how, during a party held to mark his 80th birthday in 2009, he greeted his former pupils with familiar spiky disdain. But when he rose to speak after the toasts, which included a letter of tribute from Cameron, his voice quickly fell away.

"Overcome by the emotion of the occasion he quickly sat back down, his cheeks, for the first time I had ever witnessed, wet with tears," says Dunne.

"His adoring pupils, similarly affected, rose as one, banging the table and roaring our appreciation for long minutes."

Blackett adds: "We all need mentors in life and for many of us that was Michael. It is almost impossible to fix a comma into a sentence, or frame an insult, or pronounce a word without him hovering at the back of our minds; pernickety little things that mask the bigger truth, that he was a rock to us all."

* The Enigma Of Kidson by Jamie Blackett, published by Quiller, is on sale now priced £25.