Thirteen years on and her youngest son, Prince Harry, has continued his mother's legacy with a visit to a minefield in Mozambique.
This week the 25-year-old royal spent two days with the Halo Trust – the same British charity Diana visited in Angola eight months before her death – learning about the foundation's work.
During the private visit, which was kept secret until after Harry's departure from Mozambique, the prince bravely walked through the Cahora Bassa minefields, and, after training, attached a detonator to a live mine before carrying out a controlled explosion.
"One of the de-miners had found a mine and cleared the edge of it and Harry placed a small charge against the side of the mine," said Guy Willoughby, founder and chief executive of Halo.
"It's something that requires absolute concentration, rather like the concentration I imagine he needs as a helicopter pilot."
Having inherited his mother's passion for people from all walks of life, Harry – who spent the night with the working de-miners in their tented camp - met with victims of landmine blasts, including a 14-year-old boy and a man who had lost both his eyes and one arm.
"He met Delisso, a little boy who lost his leg herding cattle, but what was even more moving was the time he spent with Mr Graciano, the blind man who lost an arm, because he spent five or six minutes holding his one hand while he talked to him, which isn't something that comes naturally to a lot of people," Mr Willoughby revealed.
"Halo is delighted that Prince Harry has come out to support us in this quest to clear Mozambique of mines – a task we could complete in the next four years…
"His mother was brilliant at getting the profile of the risk of mines globally recognized. Prince Harry clearly wishes to follow her magnificent example and is supporting the Halo Trust in its mission."
Meanwhile, a St James' Palace spokesman has said of the visit: "Prince Harry was extremely impressed by the work he saw being undertaken by the Halo team. He has heard many times over the years through his mother and during his military career of the devastation landmines cause.
"The prince is pleased to have had the opportunity to learn more about Halo's work firsthand."