The King was there. And so was JFK. Yet this party fit for a Queen was in honour of Camilla's Mum! It was the last society dance of all before London turned out the lights...

It was the last great dance of peacetime – jewels, ballgowns, tailcoated escorts and a never-ceasing flow of champagne. 

Guests of honour were King George VI and Queen Elizabeth, but there amongst the the throng was the young student Jack Kennedy, one day to rise to become the legendary President of the United States.

And it was dawn before the last stragglers went away.

And all for a surprised and somewhat bewildered 17-year old girl, Rosalind Maud Cubitt. 

Rosalind Maud Shand (nee Cubitt) daughter of Roland Cubitt, 3rd Baron Ashcombe, was the mother of Queen Camilla. Here, she is pictured in Bystander magazine in 1939, the year she was a debutante

Rosalind Shand pictured with her daughter Camilla in March 1965

Major Bruce Shand married Rosalind Cubitt at St Paul's Church, Knightsbridge, in1946

The world had come to pay homage to this shy sprig of aristocracy, but despite society's spotlight shining briefly upon her, she was never to make a name for herself.

That honour would later go her daughter, Camilla – now our queen.

Yet on that hot July night in 1939 it was Rosalind who was the centre of attention – although her, mother Sonia, said by some to the illegitimate daughter of King Edward VII, was a close rival on that and many other evenings.

When it came to flamboyance, Sonia could easily match the monarch they called Tum-Tum and was determined that no expense should be spared as she launched her daughter into society.

She'd married the rich Lord Ashcombe, though there were already cracks in the marriage which would end in divorce.

The ball was held at Holland House, set in 50 private acres in the most expensive part of London, the last grand mansion in the metropolis.

The war-clouds were already gathering - but nobody realised as they arrived that night that as the last champagne-glass was drained, high society in Britain would never be the same again. Holland House itself would be firebombed to destruction in the Blitz.

'Twenty four hours of splendour,' wrote the MP and diarist 'Chips' Channon, 'of old-world magnificence!

'Immediately we arrived we were in a jam - pink debutantes, be-tiara'd dowagers, ambassadors, royalties – all in a crowd such I've never seen. One could not dance, one could not move... eventually I found the Infanta Maria Cristina [daughter of the king of Spain] and Princess Cecilie of Prussia [daughter of Prussia's Crown Prince] and I piloted them to a room where we had some champagne.

'All London was present – I found the Queen of Spain on a sofa, while the Queen of England was with Lord Rochester. She was in white and wore a crown – but in her attempt to help the King [post-Abdication] she has become too prominent and steals his thunder.'

The fabled bandleader Ambrose brought his musicians to play the night away, and the massive Holland House gardens were floodlit for the guests to wander about.

Meanwhile, where was the star of the show? Rosalind Cubitt may have been the reason her mother Sonia threw the ball – but she wasn't deemed important enough to attend the pre-ball dinner Sonia threw.

Among the guests at her table were the King and Queen, the US Ambassador Joe Kennedy, Noel Coward, the colossally wealthy Maharajah of Jaipur and – alas – the well-meaning and entirely innocent Prince Frederick of Prussia, a Cambridge student who within weeks would be interned and packed off to as Canadian detainee camp for the duration.

Meanwhile young Rosalind was entertained by an old friend of her mother, Maria Denison, whose husband had commanded the Royal Yacht, and a genial old General, Desmond Beale-Browne.

Beale-Browne had commanded the Royal Lancers, who now counted among their young officers the 22-year old Lieutenant Bruce Shand.

History does not relate whether Bruce and shy Rosalind first set eyes on each other that night - or whether she danced with the young Jack Kennedy, in London on a break from his studies at Harvard. But the moment peace was declared in 1945, Bruce and Rosaland married.

Though many present carried away memories of the lavishness of her coming-out ball, it may all have been a bit too much for the girl herself.

For when it came time for her to launch her daughter Camilla into society in 1965, and though she was wealthy enough, she chose instead a cocktail party at Searcys' catering rooms off Knightsbridge, followed by a shared dance in Surrey.

Among the guests were fellow-debutantes Angela Nevill, who'd date Prince Charles ahead of Camilla; Lady Mary-Gaye Curzon, whose daughter Cressida Bonas would date Prince Harry; Miranda Seymour, later to be an acclaimed writer; and Sally Farmiloe, later a Howards Way actress but best remembered for her headline-grabbing affair with writer Jeffrey Archer around the time of his libel trial.

George VI and Queen Elizabeth arrive at the French Embassy in 1939

Joseph Kennedy,  Ambassador to the Court of St James, poses with his son John 'Jack' Kennedy, who would later become The President of the United States

Diarist Henry 'Chips' Channon who attended the 1939 ball at Holland House

One last deb's name on the guest-list was that of Sarah Corbett, whose father Arthur – later Lord Rowallan – would go down in history as the man who married April Ashley, one of the first sex-change pioneers.

Each of these made more headlines than the apparently unremarkable Camilla Shand - until she burst into the limelight in 1992 when exposed as the secret love of Prince Charles. Since then, of course, she's become celebrated as a successful and highly-regarded Queen Consort.

But she never had a king and queen attend her coming-out dance, or a future US president. Mother Rosalind, who died of osteoporosis in 1994, would always have that special memory.

After her last waltz, they switched out the lights. And London remained dark for nearly six long years.