- Before he got engaged to Princess Diana, Prince Charles proposed to another woman, Amanda Knatchbull.
- In Battle of Brothers: William and Harry – The Inside Story of a Family in Tumult, royal historian and biographer Robert Lacey explains that Amanda rejected Charles' proposal because she didn't want to live with the public scrutiny of a royal.
- The rejection stuck with Charles and reinforced his belief that no one should have to deal with the pressure of marrying into the Windsor family.
When Prince Charles and Princess Diana got engaged, it wasn't totally a gesture of love. Charles was under pressure from the royal family to settle down and Diana seemed liked a perfect match. But before Diana was the perfect match that Charles was pressured to propose to, there was another "perfect match" Charles was pressured to propose to: His cousin (not a first cousin, but still, yeah...) Amanda Knatchbull.
In Battle of Brothers: William and Harry – The Inside Story of a Family in Tumult, royal historian and biographer Robert Lacey explains that Charles' great-uncle, Lord Mountbatten (aka "Uncle Dickie"), had pushed for him to marry Amanda, who was his cousin and Lord Mountbatten's granddaughter. According to Lacey, Charles admitted to being "very fond of her" and a relationship did, eventually, blossom.
Lacey writes: "Over the years the two cousins did grow close, developing a mutual respect and friendship that has lasted to the present day. But when the prince finally made his proposal in the summer of 1979—shortly before Lord Mountbatten's assassination by the IRA—the independent-minded Amanda politely turned him down."
And the way Amanda turned Charles down had a big impact on the future king.
"The surrender of self to a system, she explained, was so absolute when joining the royal family, it involved a loss of independence 'far greater than matrimony usually invites,'" Lacey writes in the book.
According to Charles' biographer, Jonathan Dimbleby, the rejection "served only to confirm [Charles'] own belief that to marry into the House of Windsor was a sacrifice that no-one should be expected to make."