Long before Princess Diana and Camilla Parker Bowles married Prince Charles, he fell for a very surprising woman most of us haven't heard of.
Lady Diana Spencer and Camilla Parker Bowles, on paper, had a lot in common. Both were blonde, daughters of the English aristocracy raised in wealthy families who enjoyed the privileges that came with their class.
Both went to a Swiss finishing school and neither really ever worked. Most significantly, both were intimately involved with (and married to) Prince Charles.
All of which makes his choice of first girlfriend more surprising. While any debutante in the late 60s would have happily dated the heir to the throne, the woman who bewitched the Charles was not some blushing home counties girl wearing pearls but a quadrilingual older woman.
Meet Lucia Santa Cruz, the most important woman in the future King's life you have never heard of.
Despite graduating from his hated, austere Scottish boarding school Gordonstoun, Charles was accepted into Cambridge. Unlike other undergraduates, when the then 18-year-old arrived in October 1967, he moved in a suite of rooms not usually offered to first year students along with a specially built private bathroom. After the Queen saw her son's rooms she sent her a staff member from Sandringhim (known as her "tapissier") to bring the Prince curtains, carpets and even a duvet, while the Queen Mother sent him a painting by a favourite Scottish artist.
At the time, the Master of Trinity College was Lord 'Rab' Butler, a former Chancellor of the Exchequer. He happened to be incredibly well connected and had employed a friend's daughter as his research assistant.
Lucia Santa Cruz was five years older than Charles. She spoke four languages, had degrees from Kings College, London, and St. Antony's College, Oxford and was the daughter of the Chilean ambassador to the court of St James.
In the English spring of 1969, Butler, whether accidentally or on purpose, played cupid, inviting both his royal student and Lucia to a dinner party. Sparks flew. Charles' cousin Lady Elizabeth Anson (who was also a friend of Lucia's) commented, "She was the first real love of his life".
Charles at that age was widely known to be shy and socially awkward. Still, his relationship with Lucia progressed. According to royal biographer Tina Brown, Butler even gave a Lucia a key to the Master's lodge so the couple could meet up in private.
(In 1992, Lord Butler's wife Mollie wrote that Lucia was a "happy example of someone on whom [Charles] could safely cut his teeth, if I may put it thus".)
This was no sordid liaison but a romance. In 1971 they were photographed in London in the back seat of a chauffeur-driven car and The Telegraph reported he even took her to Balmoral to meet his family.
THE CAMILLA CONNECTION
Lucia is credited with not only being Charles' first sexual partner but also the person who introduced him to perhaps the most important woman in his life – the then Camilla Shand.
While no one quite knows why things between Lucia and Charles ended, what we do know is that in 1971 she had moved into a flat in the London suburb of Belgravia. Living in a flat below was debutante Camilla Shand and the two women became firm friends.
In his authorised biography of the Prince of Wales, author Jonathan Dimbleby says Lucia told Charles she had "just the girl" for the young prince and then arranged for the royal to meet Camilla. Almost immediately, Charles was smitten and "he lost his heart to her almost at once".
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THE DIANA YEARS
Given the integral role that Lucia played in bringing together two of the twentieth century's most controversial lovers, it is perhaps surprising that she ended up becoming one of Diana, Princess of Wales' most trusted confidants and friends.
Lucia later married diplomat Paolo Tarso Flecha de Lima, who later became Brazilian Ambassador to the UK. In 1991, Lucia and Diana met during the Wales' official trip to Brazil and later, over the course of the royals' disintegrating union, she would offer Diana solace and the chance to escape London.
On Boxing Day 1993, after spending Christmas Day absolutely alone, Diana flew to Washington to spend a week with Lucia. The 31-year-old was in a particularly vulnerable place, telling biographer Andrew Morton that "I cried all the way out and all the way back, I felt so sorry for myself".
Despite her closeness to Diana, Lucia remained close to Charles also, with the Prince becoming godfather to her eldest son.
Despite Lucia's closeness to Diana, she has also remained close Charles and Camilla. In 2009, when the Prince and the Duchess of Cornwall embarked on an official tour of South America, they visited Lucia in Lima; in 2011, she was invited to the Duke and Duchess of Cambridge's wedding and in 2014, Camilla attended a London charity function organised by Lucia.
Unlike other women in Charles' orbit, Lucia forged a highly successful career and remains
a prominent figure in her native Chile as an established historian and academic, along with having served on the board of the Santander bank, the Chilean TV station TVN and assuming the prestigious role of Dean of Liberal Arts at Universidad Adolfo Ibáñez.