Princess Diana’s Cause of Death: How Did the Beloved Royal Pass Away?

It’s been nearly two decades since Princess Diana died on Aug. 31, 1997. While the sadness of her tragic passing has never faded, many have forgotten how the beloved royal’s life was cut short at the age of 36.

One year after she divorced Prince Charles — the father of her two sons, Prince William, now 35, and Prince Harry, now 32 — Diana died in a fatal car crash. According to an official police report obtained by the UK’s Sunday People in 2014, the mom-of-two was unlawfully killed due to the negligence of chauffeur Henri Paul, who had been speeding away from pursuing paparazzi after leaving the Ritz Hotel.

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Henri (who had been driving under the influence) and Diana’s boyfriend, Dodi Al Fayed, were also killed in the collision. The only surviving passenger was bodyguard Trevor Rees-Jones. Not long after the accident, Dodi’s father, Egyptian billionaire Mohamed Al Fayed, claimed that the crash was orchestrated by the British government. “This is not an accident,” he said at the time, igniting years of conspiracy theories about Princess Di’s untimely death. “It is a plot, an assassination.”

Diana, William, and Harry. (Photo Credit: Getty Images)

As the 20th anniversary of Diana’s death draws near, she will be remembered in several upcoming documentaries — including HBO’s Diana, Our Mother: Her Life and Legacy, which is set to premiere on Monday, July 24 at 10.p.m. EST. William and Harry — who were age 15 and 12, respectively, when their mom died — sat down together for the film to reflect on their mom’s legacy and her fun approach to parenthood.

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“She was one of the naughtiest parents,” Harry recalled in the movie. William echoed his younger brother’s remarks, saying, Diana “was very informal and really enjoyed the laughter and the fun” of raising two boys, and “understood that there was a real life outside of the palace walls.”