In 1947, the Queen wrote a two-page letter to her friend, Betty Shew, reflecting on her relationship with Philip and why they got on so well.
“We both love dancing – we have danced at Ciro’s and Quaglino’s as well at parties,” writes the then-21 year old princess.
“Philip enjoys driving and does it fast! He has his own tiny M.G which he is very proud of – he has taken me about in it, once up to London, which was great fun.”
The Queen also recalls how she and her future husband met.
“The first time I remember meeting Philip was at the Royal Naval College, Dartmouth, in July 1939, just before the war. (We may have met before at the coronation or the Duchess of Kent’s wedding, but I don’t remember).”
She also tells her friend how Philip even played a part in his choice of engagement ring for her.
“The engagement ring was made by Antrobus. Princess Alice took it in as Philip obviously couldn’t but he designed the ring,” she writes.
The Duke and Duchess of Windsor’s intense love for each other was apparent in the letters they wrote to each other during the abdication crisis.
“Darling, Sweetheart,” Wallis once wrote to the king. “I feel as though my heart would burst if I didn’t see you. But we must be brave and keep sane for a few more months.”
The king began his replies, which were often sent several times a day, “Oh my beloved”. In one he gushed, “I feel like bursting tonight with love and such a longing to hold you tighter than I ever have before”.
He continued, “You see, I do love you so entirely and in every way, Wallis, madly, tenderly, adoringly and with admiration.”
On the day they got engaged, Victoria wrote a series of love letters to her future husband, Prince Albert, telling him how passionately she felt for him.
“I am so touched by the evidence of trust that you give me in sending your letters, and by the so affectionate sentiments that you express towards me therein, that I scarcely know how to reply to you,” the 20-year-old wrote. “How have I earned so much love and so much warm-hearted kindness?”
She went on to explain how happy she was to have found him.
“I am still unable to accustom myself to the truth of all that I see and hear and can only believe that Heaven has sent down an angel to me, whose radiance is intended to brighten my life,” she continued. “May I succeed in making you quite quite happy, as happy as you deserve to be!!”
Albert was Victoria’s first cousin and the son of her mother’s brother and because Victoria was monarch, she proposed to him.
In 1989, private correspondence between Anne and the then-Queen’s equerry, Timothy Lawrence were stolen and sent to British newspaper, The Sun.
The contents of the letters were never revealed but were described as too “steamy” to print and the scandal spelled the end of the Princess’s marriage to Captain Mark Phillips.
By 1992 Anne and Mark had divorced and she and Timothy went public with their relationship.
They married in December and have been together ever since.
In a letter to Camilla on the day of their 2005 wedding, Charles expressed his heart-felt feelings for his long-term love and revealed a dry sense of humour.
“You know what I’d really like to say to you, but given our exchanges have in the past fallen into the wrong hands with decidedly embarrassing consequences,” Prince Charles wrote in the 2005, likely alluding to their infamous taped telephone conversations of the early Nineties.
“I’ll keep this one on a friendly, but formal footing if it’s all the same to you, dear sugar lump.”
He continued to write about how he felt he could be himself with Camilla, noting, “But you, my dear: you are different. Hang it all, raisins to my nuts, with you I feel I can talk about biodegradable Wellingtons for hours without the other party rolling their eyes,” the future king added. “Your tin whistle, ‘pon which a merry tune of love you play.”
In a collection of deeply romantic and emotional letters written in the early Nineties from Camilla to Charles, the now Duchess of Cornwall wrote that her “heart and body aches” to be with him.
Camilla says to the man she calls, “my most precious darling” that “I yearn to be with you day and night, to hug, comfort and love you”.
The emotional letters were unearthed by the Daily Mail in 2004 and had been originally found by Princess Diana who then passed them on to her biographer Andrew Morton.
In them, Camilla also urges Charles not to feel guilty about their affair – they were still both married to other people at the time – and promises to be his “forever”. She also describes Diana as “that ridiculous creature”.
The Princess of Wales was famous for being an enthusiastic letter writer and in 2002, her former lover, James Hewitt put a number of the ones she’d sent him up for sale.
On March 4, 1988, she wrote, “Dearest James, you have left and it all feels very empty here to me and that includes one bottle of champagne, too!”
Their relationship began in 1986 but had ended by the end of the decade when the army guard took up a position in Saudi Arabia.
Two years ago, Diana’s letters to her boyfriend Dodi Fayed, who died with her in the 1996 Paris car crash, were published. The royal’s August 6, 1997 letter was written soon after their south of France holiday together.
“Darling Dodi, Heaven knows where on earth I begin to thank you for the most magical six days on the ocean waves,” she wrote.
“It is a bit of an Oh my God situation. I adored it all and every possible minute was full of laughter and happiness, and that combination is a serious treat.”
She signed off: “This comes with all the love in the world and, as always, a million heartfelt thanks for bringing such joy into this particular chick’s life, from Diana xx”.
For more, pick up the latest issue of New Idea Royals.