Princess Diana's first Trooping the Colour ceremony at 19 which ended in disaster

Princess Diana made her first appearance at the Trooping the Colour ceremony to mark the late Queen's birthday back in 1981 when she was just 19-years-old, but unfortunately the day took a disastrous turn.

The grand event is held annually on the second weekend of June for the monarch's official birthday regardless of their actual date of birth, as King Charles prepares for his celebrations this weekend despite being born in November.

The Trooping the Colour ceremony is typically a time when royals gather on Buckingham Palace's balcony to marvel at an indomitable RAF fly-past following a parade that moves from the Palace down to The Mall before finally reaching Horse Guard's Parade.

While generally happening without a hitch, Princess Diana's inaugural presence in 1981 was unfortunately marred by an unexpected incident, OK! reports.

Prince Andrew accompanied Diana, then only 19, in a carriage while her soon-to-be spouse, Prince Charles, participated on horseback.

The late Princess of Wales wore a bespoke blue floral suit designed by Bill Pashley for the event - which occurred only one month prior to Lady Diana Spencer, as she was formerly known, exchanging vows with Prince Charles in an opulent ceremony at St Paul's Cathedral.

Her presence broke royal protocol's "no ring, no bring" rule, but it soon became apparent that there were far more significant issues at hand that day.

The day of the ceremony was gripped by terror as Marcus Simon Sarjeant, a 17 year old lad, fired six blank shots towards Her Majesty, Queen Elizabeth II, while she was riding along The Mall on her horse, Burmese.

Despite this alarming incident, the monarch, who was 55 years old at the time, exuded calm and courage as she continued her horse ride.

Following the attempted attack, the schedule carried on without further disruption as Her Majesty returned to Buckingham Palace through the same route under extra-tight security measures.

The young man, upon his arrest, shockingly confessed: "I wanted to be famous. I wanted to be a somebody."

Immediately after this confession, he faced prosecution under the Treason Act of 1842 and consequently received a prison sentence lasting five years.

Amidst the unsettling events of the day, the ceremonial proceedings were resumed with no more interruptions, as Princess Diana was seen standing amongst other Royal Family members observing the fly-past from the balcony of Buckingham Palace.

However, it's worth mentioning that the upcoming wedding of Charles and Diana fuelled additional security worries at St Paul's Cathedral in anticipation of a potential repeat occurrence.

Thankfully, the awaited wedding proceeded smoothly without any reported security lapses.

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