In 1997, the Princess of Wales made a high-profile visit to a landmine clearance programme in Angola. Her trip is credited with boosting the campaign for a global landmine treaty signed later that year. Also, the man who rewrote the rules on transitions of power in the USA, the first woman to wear a headscarf into the Turkish parliament and the triumph of British espionage that changed the course of World War One.

PHOTO: Princess Diana in Angola in 1997 (Credit: Alamy)