24 February 1981: Prince Charles and Lady Diana Spencer announce their engagement

By the 1980s, Prince Charles was getting on a bit. He was 31, and still hadn't lined up a suitable bride to produce heirs. He'd played the field, following the advice of his great uncle, Lord Mountbatten, who believed a man "should sow his wild oats and have as many affairs as he can before settling down".

Mountbatten also had clear cut ideas on marriage material. "For a wife", he said, a man should find "a suitable, attractive, and sweet-charactered girl before she has met anyone else she might fall for". So that's what Charles did.

While courting Lady Sarah Spencer, her younger sister Diana caught the prince's eye. She was, he would later admit, a "jolly, amusing and attractive 16-year-old – bouncy and full of life". And so three years later, once she'd reached a more respectable age, Charles set about wooing her.

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By then, she'd found work as a nursery teacher, and as speculation grew, the world's paparazzi followed her around London has she pootled between home and work in her Mini Metro.

The couple went to polo matches, went sailing, and Diana was taken to meet the future in-laws at Balmoral. Having received the approval of the Queen, Charles proposed on 6 February 1981. And on this day that same year, they announced their engagement to the world, where they showed off the ring – a 12-carat sapphire surrounded by 14 diamonds.

Diana wowed the country. Asked if they were in love, Diana immediately replied "Of course!" Charles, however, proving what a gauche buffoon he really is, said "whatever ‘in love’ means", thereby annoying pretty much all right-thinking people.

They were married on 29 July 1981. The day was made a public holiday, and 600,000 people turned out to line the streets, while 750 million watched the whole thing on TV.