In 1979 I wrote a book called Class. It caused an uproar. I did lots of wireless interviews and everywhere I went, terrifying-looking young DJs with studs and nose rings would demand to know what class they were and I would nervously lie that they were upper-middle class. Lord Montagu led the miners against me on a television programme — they shouted at me that I was an evil cow for suggesting the class system still mattered.

Not long afterwards I was at a party at Hatchards in Piccadilly. The Duke of Edinburgh came rushing over to me and said didn’t I realise the class system no longer existed. I told him that according to the 1971 census his daughter Princess Anne, as an event rider, was in the same social class as a gamekeeper, social class III (manual). “Rubbish,” he snapped. “Keepers are working class.”

Even though we like to talk about a classless society, people still get apoplectic about class. Just look at the row over Jade Goody and Shilpa. And now the unpleasant attacks made on poor Kate Middleton’s mother. Instead of just accepting the obvious, that here were two gorgeous young people who met too young, the separation has turned into an excuse for a lot of horrible sniping about whether the Middletons were good enough for the royal family.

Carole Middleton is supposed to have said “Pleased to meet you” instead of “How do you do” when introduced to the Queen and to have chewed gum at William’s passing-out parade. Well, she might have had garlic for lunch, mightn’t she? If so, it would be rather good manners to chew a bit of peppermint gum.

And the Queen is far too kind and wouldn’t have given a stuff how Mrs Middleton introduced herself. She and the royal family don’t know anything about social nuance and all the things we run around with at the lower levels. That sort of snobbery is all about jockeying for position on the next rung down from royalty and all the way down from there.

Prince Charles and Camilla, who live near me in Gloucestershire, are again far too kind to be snobbish. They wouldn’t dream of hurting anyone that way. All this is not just a stick to beat Mrs Middleton with, it’s a stick to beat the royal family with too, as it’s meant to suggest they care about all that.

I’ve never met Prince William but everyone I know around here who knows him says he is a charming boy, with no side at all. His mother, Princess Diana, was totally unsnobbish.

His friends are supposed to have looked down on his girlfriend’s mother because she was once an air hostess. Well, in my day, back in the dark ages, we all longed to become air hostesses, because that’s how you met gorgeous men. I got turned down for the job because I was too fat and scruffy. But airports were glamorous places and if you had a bit of zing about you that’s where you wanted to be.

But it all goes to show that class isn’t dead. It reminds me of the true story about the aristocrat being treated for depression by the psychoanalyst. The sessions were going nowhere and in exasperation the psychoanalyst said: “Tell me exactly what you’re thinking about right now.” And the aristocrat replied: “I was just thinking what a vulgar little man you are.” And the sessions collapsed because the psychoanalyst felt he’d lost all ascendancy.

Dame Barbara Cartland famously replied, when the television journalist Sandra Harris asked her in the 1960s whether class barriers had broken down: “Well, of course they have, otherwise I wouldn’t be sitting here talking to someone like you.”

Most of the outward signs have gone. When we arrived here 25 years ago I was told it was irredeemably common to have red flowers in a Cotswold garden. Now nobody cares about anything as long as you pay your local bills and don’t hurtle down the village in your shining Chelsea tractor, scraping the paint off parked cars.

But one thing likely to give you away as non-U these days is political correctness because it’s so euphemistic. The aristocrat tends not to be politically correct. In fact he’s generally a randy old sod whose family has spent 700 years fornicating and shooting things. If a girl’s got a pretty face, he won’t care what class she’s from.

But if you start referring to your “partner”, or “lone parents”, or people being “vertically challenged”, you will be instantly marked out as non-U. The papers said Prince William had telephoned Kate during all the furore and been very “supportive” — another dreadfully non-U word. Soon they’ll be rabbiting on about them “achieving closure”, another horror.

There’s a lot of confusion about class. Most of the Labour party thinks Tony Blair is terribly grand, but he isn’t. He’s charming, of course, but very, very middle class, not even upper middle class. And I’ve found out while researching Wicked!, which is set in schools, that among young people the word “posh” often isn’t used to denote class, but to accuse someone of being irritatingly clever. Perhaps people who are “posh” are destined to do well in exams and make it to the top.

Class has given us great comic characters, from Mrs Bennet and Hyacinth Bouquet to Tim Nice-But-Dim and Vicky Pollard, the archetypal working-class girl, mouthy, inarticulate and terribly funny.

It’s much more fun to have a class system than not, as long as everyone can go on gently laughing about it. The thing that’s horrid is when people feel hurt by it. But you should remember that the royal family isn’t nearly as old as half the aristocracy — so a lot of people look down on them, too!

www.jillycooper.co.uk

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