Royals See Princess Diana's Dramatic First Trooping the Colour — 1 Month Before Marrying Prince Charles Lady Diana Spencer made her Trooping debut in 1981, one month before tying the knot with Prince Charles By Dana Rose Falcone Published on June 9, 2018 05:14 AM Share Tweet Pin Email Unlike Kate Middleton and Meghan Markle, Princess Diana attended her first Trooping the Colour prior to marrying into the royal family. Diana, then only 19, made her Trooping debut one month before tying the knot with Prince Charles in June 1981. Kate and Meghan, however, got engaged between Troopings, which typically have a “no ring, no bring” policy. Saturday marks Meghan’s Trooping debut since Prince Harry proposed in November and the couple got married last month. When Diana stepped out at her first Trooping the Colour, the princess-to-be wore a custom Bill Pashley blue floral suit that she’d requested from him when they met in May of that year. Diana held herself with poise as she rode in a horse-drawn carriage with Prince Andrew, since Charles rides on horseback as a royal colonel of the Household Division. Can’t get enough of PEOPLE’s Royals coverage? Sign up for our newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! Jayne Fincher/Princess Diana Archive/Getty But the day — meant to serve as the Queen’s official birthday celebration — took a dark turn when 17-year-old Marcus Simon Sarjeant fired numerous pistol blanks at Queen Elizabeth while she was on horseback riding along The Mall to the ceremony. Sarjeant emerged from the crowd and fired at least six times before being wrestled to the ground by police. The former cadet allegedly told them, “I wanted to be famous. I wanted to be a somebody.” RELATED VIDEO: Royals Flashback: 18 Iconic Princess Diana Moments The Queen, then 55, remained uninjured, offered her 19-year-old horse Burmese a reassuring pat and rode on “as cool as a cucumber as if nothing had happened,” her former guard Alec Galloway recalled to Sky News. Once the situation was under control and Sarjeant was charged under the Treason Act of 1842, the events continued as planned, with Diana joining the royal family on the Buckingham Palace balcony for the first time. BOB DEAR/AP/REX/Shutterstock The incident raised security concerns for Diana and Charles’ wedding the following month at St. Paul’s Cathedral, especially because Sarjeant — who was sentenced to five years in prison — was said to be seen wearing a Charles and Diana wedding button on the day of the Trooping event. Tim Graham/Getty But the big day came and went with no security issues, and the newlyweds became the first royal couple to kiss for the crowds on the Buckingham Palace balcony after their wedding ceremony.