From fairytale wedding to Royal tensions: How Prince Harry's birth changed Charles and Diana's marriage

A wedding of epic proportions, the marriage of a future King to his charming young bride was hailed as the ceremony of the century. A whirlwind of grandeur and romance swept across the world on July 29, 1981.

An astounding 750 million viewers from across 74 nations tuned in to watch Lady Diana Spencer exchange vows with then-Prince Charles at St Paul's Cathedral, officially becoming the Princess of Wales.

All around London, about 600,000 enthusiasts thronged the avenues, eagerly witnessing their historic union that surprisingly materialised a mere five months post their engagement. Diana revealed having met Charles only 13 times prior to their monumental day.

The spectacle of bride stepping out of her horse-driven carriage onto the cathedral's steps had the world holding its breath. She flaunted "the most closely guarded secret in fashion history" - her wedding dress.

This lavish wardrobe piece was an iconic ivory silk and antique lace gown embellished with over 10,000 pearls and boasted of a majestic 25-foot train. Speaking about her creation, designer Elizabeth Emanuel said it was intended to make Diana "look like a fairytale princess", reports the Mirror.

Post the ceremony, the new couple were spotted waving and beaming in an open carriage, navigating through the thrilled crowd assembling towards Buckingham Palace. The ordinarily composed Charles was seemingly so tense during the service that he missed out on giving Diana a kiss after taking his vows.

However, he compensated for this oversight on the Royal balcony, thereby kick-starting a regal custom.

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Just three months into matrimony, the newlywed royals embarked on their inaugural engagement - a whistle-stop three-day tour of Wales that took place in October. It was during this excursion that Britain's sweeping fondness for the fresh-faced Princess became glaringly apparent, evidenced by chants of "We want Diana! " whenever Charles approached instead.

The subsequent year bore witness to the birth of their first child, William, and resulted in a monumental surge in popularity for the Royal Family, levels not recorded in many decades past. Noted Royal biographer Penny Junor portrays a picture of household joy in that era: "People who visited Kensington Palace in the early 1980s describe Diana charging about the house playfully looking for William who had run away and hidden under his father's desk at bedtime. Others describe Charles chasing Diana up the stairs. I think there were definitely good times."

The dawn of March 1983 marked another momentous occasion as Diana, a tender 22-years-old, embarked on her very first overseas expedition which also happened to be her maiden trip abroad. Accompanied by Charles and baby William for over 40 days in Australia and New Zealand, it was an iconic tour that unequivocally cemented Diana's already soaring stardom well above that of her husband's, the future king.

However, whilst the tour was heralded as a success among Royal circles, later allegations suggest that the intense publicity and public admiration heaped upon Diana sowed seeds of tension within their marriage. Diana's biographer Andrew Morton subsequently penned: "In public, Charles accepted the revised status quo with good grace; in private he blamed Diana."

However, the couple maintained an image of being deeply in love, often capturing romantic moments that included hand holding and a famed amorous dance at a gala dinner in Sydney. Exactly one year after, Princess Diana gave birth to their second son, Harry.

Within the first four years of their marriage, the princess flawlessly adhered to her Royal commitments, presenting an heir and a spare, all while aiding in upholding The Firm's popularity and relevance. However, drastic changes were seen following Harry's birth, as Diana expressed to Morton: "Suddenly as Harry was born it just went bang, our marriage, the whole thing went down the drain. Something inside of me died."

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