Ascot Ladies' Day
The flower of British femininity: Ladies' Day at Ascot Getty Images

It is extraordinary to think that when Queen Elizabeth II ascended the throne in 1952 Sir Winston Churchill was Prime Minister, there was still post-war rationing, debutantes were presented at court wearing the white dresses of purity, divorcees were barred from the Royal Enclosure at Ascot, much of the map of the world was coloured British Imperial red, there was only one television channel, a pint of milk cost four old pence and the telephone was a luxury, bizarrely attached to the wall.

It seems as remote as when dinosaurs roamed the earth. Yet during the most cataclysmic change in history Elizabeth II has remained, in the words of that rock star writer William Shakespeare at the court of the first Elizabeth, "an ever- fixed mark that looks on tempests, and is never shaken".

The changes have been social, financial, sexual, moral, religious, political, sociological and, above all, technological. Since the Fifties the Royal Mail has been trumped by email and we even have ER-mail: the Queen is on Facebook and Twitter (@Queen_UK since you're asking). Never, in any period of history, has change been so rapid and far-reaching.

Socially we have moved, although not necessarily progressed, from an era in which doing the Done Thing was an essential for how to get on in society to the Dunno' Wotever, a prerequisite for the don't care, laissez-faire society.

You could measure out the Queen's 63 years in cutlery and how to use it. In 1952 gentlemen – and to be one was a state of grace not a lavatory – knew how to hold their knives and eat their meals from the outside of the silver place setting inwards. In 2015 knives are, in the age of takeaways, virtually surplus to requirements, let alone strictures on whether or not you hold the damn thing like a pencil and are therefore a peasant.
In the houses of the vast majority of Her Majesty's subjects Mrs Patmore is no longer in the kitchen. "I'm afraid we are very suburban and have our supper on a tray in front of the television," the Earl of Cork and Orrery confided apologetically. And who is to say that telly supper isn't the done thing, or perhaps the dine thing, in Buckingham Palace? The Duke of Edinburgh attended an opening at the Rountree Tryon Galleries in St James's in March and stayed half an hour longer than expected. "Very surprising," said his equerry. "EastEnders is starting in a minute."

The Done Thing in 1952 was that no divorcees (divorce being the undone thing) were allowed into the Royal Enclosure at Ascot and debutantes (the marriageable daughters of good families) were presented at court. Prince Philip immediately had a go at these anachronisms: divorcees were admitted to the Royal Enclosure in 1955 and the presentation of debutantes ceased in 1958, chiming with the aftermath of the Suez Crisis which effectively ended British imperialism. The previous year Lord Altrincham had pronounced the ritual of the court presentation embarrassing, saying it should have been quietly discontinued after the war to make "a truly classless court".

It was a mercy to put it down: beady and needy aristocrats like Lady St John of Bletso were accepting money to bring out aspiring girls, Princess Margaret said, "We had to put a stop to it. Every tart in London was getting in", and The Queen and Prince Philip were spared hours of boredom having vapid youth curtseying to them (as taught by Madame Vacani, doyenne of the aristocrats' dancing classes), then giggling and pigging over the Palace's chocolate cake.

We now view this social change as a rosy dawn: rock 'n' roll instead of Madame Vacani, the Beatles (whom one's mother thought such nice young men) getting the MBE, John Osborne's Look Back in Anger (one's mother was not so keen on kitchen sink drama, quite enough of that at home) and angry young men who nevertheless wore ties even if their shirt collars were unbuttoned.

Queen Elizabeth II: The life and legacy of Britain's longest reigning monarch IBTimes UK

Yet the rump of society clung to the wreckage by its finger nails. Queen Charlotte's Ball, a social Nuremberg rally – what Jessica Mitford called "the specific, upper-class version of a puberty rite" – continued as it had done for 200 years since Queen Charlotte, wife of King George III, had received hopeful candidates on the marriage market of an exclusive gene pool. Debutantes, still in white, now curtseyed to a cake. I came out in 1970 and we were still curtseying to a cake and still wearing white (despite the Pill having made that a nonsense) and Lady Carina Fitzalan-Howard, with whom I'd been at school, trod on the silk train of my dress – ironically she later married David Frost, architect of so much new Elizabethan change as the star presenter of That Was The Week That Was, the revolutionary satire show produced by Ned Sherrin. Sherrin later received the CBE and Frost a knighthood – the naughty boys made good.

Gargoyles like Mrs Betty Kenward (Jennifer of Jennifer's Diary in Harpers & Queen) and Peter Townend of Tatler guarded the flame of formal society. A list of the parties of the season was published on the Court and Social page of The Times: "Mrs Peter Mather At Home for Victoria ... " If you did that now on Facebook – the modern Court and Social – hundreds of hopeful uninvited guests would crash for the lemonade and weak Pimm's.

Julian Fellowes (now Lord Fellowes of West Stafford, or Downton Abbey as we prefer to call him) was the chap around town. He was safe in taxis, charming to one's parents and now, over 30 years on, has a hit about ... class. If anything illustrates the weird fascination with the old order it is the success of Downton Abbey. We may have become classless but we miss it. It was another country, we did things differently there – and it was rather fun.

The reluctance of the aspirant upper middle classes to let go of the The Season – the Royal Academy exhibition (where no one looked at the art); the Chelsea Flower Show (where no one looked at the flowers); Royal Ascot (where no one looked at the horses); Henley Regatta (where no one looked at the boats); Cowes Regatta (where only the men got on a boat), and the grouse in Scotland (which only the men shot) – was an immutable pattern. Everyone hates change, particularly for the better. Princess Margaret would definitely consider that every tart had got into Ascot judging by the press coverage of the absurd fashions and overt alcoholic consumption.

Essentially this old order has been rendered irrelevant by the cult of celebrity sweeping away aristocracy. Not everyone can be a duke's daughter, that is an accident of birth, but everyone can aspire to 15 minutes of fame on a reality television show. Made in Chelsea precisely mocks the old order by putting so-called posh young men and women in the reality situation; The Only Way is Essex trounced Downton Abbey for a television award.

A certain element of what goes around comes around: at the beginning of the Queen's reign the "supermodel" was the aristocratic Bronwen Pugh, then we went through Twiggy and Jean Shrimpton to Naomi Campbell and Kate Moss. Today it is aristocratic Cara Delevingne (her grandmother was lady-in-waiting to Princess Margaret) who nevertheless behaves in a celebrity way with 10.3 million Twitter followers and an Instagram account for her pet rabbit.

The apex of this social earthquake was the Princess of Wales who transcended aristocracy to become a celebrity. Fragile, volatile, beautiful, the object of mindless adoration, one dreads to think of social media's consequences for her. She died pre-Facebook.

So what of the Queen's courtiers? They are the heartbeat of Buckingham Palace. She relied on Sir Winston Churchill, who was a mentor to her as Lord Melbourne was to the young Queen Victoria. Lady Susan Hussey, so treasured that she is godmother to Prince William, is a Woman of the Bedchamber and confidante. Nothing changed there. The late Lord Plunket, deputy master of the Royal Household (1954-75) was the nearest the Queen was said to have had to a brother. He is buried at Frogmore in the Royal Family's private burial ground and the Queen, unusually, went to both his funeral and his memorial service at the Guards' Chapel.

What is fascinating is the modern element among the old guard. The immensely elegant Earl of Airlie (Eton and the Guards, brother Angus married to Princess Alexandra) resigned from Schroder's in 1984 to become Lord Chamberlain to the Royal Household, as his father had been to the Queen Mother. He was Lord Chamberlain at the time of the death of Diana, Princess of Wales and had the genius idea of providing the huge television screens for the crowds throughout Hyde Park.

The current Lord Chamberlain, the Earl Peel, is married to the Hon Charlotte Soames, the granddaughter of Sir Winston Churchill (what goes around comes around) and is a relatively young blood employed because he is close to the Prince of Wales and when the fatal moment comes Lord Peel will break his staff of office over the monarch's grave and say "The Queen is dead, Long Live the King!". The first staff of office of the Lord Chamberlain for the new reign will then be handed to King Charles III. Lord Peel is the great-great-grandson of Prime Minister Sir Robert Peel – what could possibly go wrong? His is the task of doing those luncheons at Buckingham Palace that now include Oscar winners with trade union leaders.

Politically the Queen is a wild card. Her job is never been to express an opinion but always to be there. Many of her court have been old friends like Lord Tollemache, with whom she and Prince Philip stay every year in Suffolk for shooting. Lady Tollemache gets the village in to help serve at table. It once went a bit wonky when the daily, having had a little bit of the cooking sherry, gave The Queen a poke in the ribs for a second helping of pudding saying: "Treat yourself, Your Majesty!"

The Queen talks most days to her cousin, Lady Elizabeth Shakerley, a descendant of the Queen Mother, who has been party planning for years to the gentry and the Royal Family. There were stalwarts like the late Lord Charteris (he who called Sarah, Duchess of York "Vulgar, vulgar, vulgar"), Lord Fellowes (a chap in a awkward position, being brother-in-law to Diana) and the Duke of Devonshire, Her Majesty's Representative at Royal Ascot. These were all safe bets, what Queen Mary called "Eton, Oxford and so to bed".

We currently have an Old Etonian Prime Minister who went to Oxford which, even if the Queen is more comfortable with her own tribe, seems anachronistic given the way modernity has been on fast forward throughout the reign. There was huge debate over whether the Coronation should be televised in case people in public houses watched with their hats, yet by 1969 the monarch was colluding with the BBC for the documentary letting a little light in on the magic of seeing that the Queen could actually cook a sausage on a barbecue at a picnic at Balmoral. (Later, in the Eighties, Her Majesty used to get rather annoyed with Mrs Thatcher for trying to help with the washing up).

Television and the press have been intrusive as never before during this Elizabethan age. The wedding of the Prince of Wales and Lady Diana Spencer was watched by a record global TV audience – but what a difference between two weddings and the Princess of Wales's funeral. For the marriage at St Paul's Cathedral in 1981 royal correspondents received embargoed information packs couriered at 6am; for the wedding of William and Catherine the details about her Alexander McQueen outfit hit our laptops via Facebook as she stepped out of the carriage at Westminster Abbey. At one point the funeral was going to be private until the public outcry became overwhelming.

The Queen's ability to adapt to change had been her strength. She has been publicly humiliated by press intrusion, from larky pictures of Diana and Sarah, Duchess of York, crashing Annabel's night club dressed as police to having to assuage international fury by a television address after Diana's death. (Tony Blair's idea as spun by Alastair Campbell). She has remained remarkably unfazed by the stupendous changes and unfortunate scandals during her reign.

She is, of course, mindful of history. Previous monarchs have led scandalous lives (Henry VIII and William IV to name but two) yet she is here to prove that change and scandal have failed to damage the institution of monarchy in the past and if technology is the future it must be made to work for the institution even if the odds seem against it. Mobile telephones have made life less safe (phone hacking) if more convenient. Email, 24-hour rolling news, wifi, the Mail online, websites, selfies: sometimes Her Majesty, the first monarch to fly supersonically, must wonder what is going to whizz along to irritate her next.