King Edward VIII caused a constitutional crisis in 1936 when the newly-crowned monarch made clear his intention to marry Wallis Simpson.
But why exactly was Wallis a controversial pick for Edward to wed and what led to the King's decision to abdicate from the throne just months into the role? Read on to find out all about the Duchess of Windsor, the woman who stole a King's heart…
And in the clip below, see inside the couple's secret photo albums, which HELLO! exclusively saw back in 2015.
Her early life
Bessie Wallis Warfield was born 19 June 1896 to Teackle Wallis Warfield, a former Baltimore mayoral candidate, and Alice Montague, the daughter of a stockbroker. The youngster was born in Blue Ridge Summit, Pennsylvania and she faced a very early family tragedy with her father dying from tuberculosis just months after her birth.
Wallis was subsequently raised by her mother and her education was funded by her uncle, Solomon Davies Warfield, who ensured that the youngster was able to attend Oldfields, the most expensive girls' boarding school in Baltimore.
In April 1916, Wallis was visiting her cousin, Corrine Mustin, when she met US airman Earl Winfield Spencer Jr. The couple enjoyed a whirlwind romance, with the pair tying the knot in November 1916, just months after meeting.
However, their marriage wasn't to last with their union being marked by long periods of separation due to Earl's career alongside his alcoholism. The couple divorced after 11 years of marriage, ending their union in 1927.
Shortly after the end of her marriage, Wallis became involved with shipping executive Ernest Aldrich Simpson, who left wife Dorothea in order to walk down the aisle with the heiress in 1928. The couple wed in Chelsea and began living in Mayfair, however, in 1937 the couple were granted a divorce, with Wallis citing adulty on Ernest's part.
Why did King Edward abdicate?
Wallis and King Edward met in 1931 when the royal was still the Prince of Wales. Wallis met Edward through her friend Consuelo Thaw, who was the brother of one the royal's mistresses at the time. It's believed that Wallis and Edward started seeing each other in 1934, although Edward denied this to his father, King George V.
The pair were together in 1935, with Edward presenting Wallis at the royal court, however, her appearance caused a scandal due to her status as a divorcee. By the time Edward ascended the throne, Wallis had divorced her second husband, and the new King made clear his intentions to marry her.
However, due to his role as head of the Church of England, a conflict arose as the church didn't agree with remarriage if the former partner was still alive. The proposed marriage was also opposed by the British government, then led by Stanley Baldwin, and the governments of the Dominions. It was made clear to Edward that if he married Wallis against the government's wishes, it would be forced to resign, which would also conflict with the royal needing to be seen as politically neutral.
Edward made the decision to abdicate, saying in a statement that he could not continue as monarch "without the help and support of the woman I love". He signed the Instrument of Abdication on 10 December 1936 in the presence of his three brothers.
Wallis's marriage to King Edward
Edward and Wallis reunited following her divorce and married one month later on 3 June 1937, which would've been the 72nd birthday of Edward's father, King George V. No members of the royal family attended the wedding.
Following his abdication, Edward was made the Duke of Windsor, and Wallis subsequently became the Duchess of Windsor after their marriage, however, letters patent issued by King George VI prevented Wallis from gaining Edward's style of 'Royal Highness'.
The couple initially lived in France, however, following the outbreak of World War II and Germany's invasion of the country they moved first to Spain and then Portugal, before moving to the Bahamas in 1940, where Edward was named Governor and Wallis became his governor's consort.
Following the defeat of the Nazis, the couple moved back to France and in 1952 settled into Villa Windsor in Paris, which would become their home for the rest of the lives. The pair would spend their days travelling between Europe and the United States on ocean liners.
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Their trips to the UK were sparing, with the pair returning in 1965 so Wallis could have surgery for a detached retina. They also attended a memorial service for Princess Mary and the unveiling of a plaque marking the centenary of Queen Mary's birth.
Wallis Simpson's later life
Wallis became a widow on 28 May 1972 when Edward died from throat cancer. The Duchess travelled to the UK for Edward's funeral and stayed at Buckingham Palace, but she became reclusive when she returned to France.
Wallis would begin suffering from dementia and in 1980 she lost the ability to speak. The Duchess died just three months shy of her 90th birthday on 24 April 1986, with the cause of death being noted as bronchial pneumonia.
Wallis's funeral was held on 29 April 1986 and the service was attended by the late Queen and Princess Alice, alongside other members of the royal family, including the then Prince Charles and his wife, Princess Diana.
The Duchess was buried alongside her late husband at the Royal Burial Ground in Frogmore, Windsor.