Marshal of the Diplomatic Corps

Her Majesty's Marshal of the Diplomatic Corps is a senior member of the Royal Household of the Sovereign of the United Kingdom. He is the Queen's link with the diplomatic community in London, arranges the annual diplomatic corps reception by the Sovereign, organises the regular presentation of credentials ceremonies for ambassadors and high commissioners, and supervises attendance of diplomats at state events. Marshals generally hold office for ten-year terms and are normally retired senior military officers, though the last three marshals have been diplomats. The marshal is assisted by the Vice-Marshal of the Diplomatic Corps, the First Assistant Marshal, and other assistant marshals.
The office was created as recently as 1920 to replace the former Master of the Ceremonies, an office dating from c.1620. Before 1920, the Vice-Marshal was known as the Marshal of the Ceremonies.
The Marshal of the Diplomatic Corps is, along with the Queen's Equerry, expected to walk backwards discreetly when leaving the presence of the monarch. They are the only two visitors who are expected to do this today, as the ancient tradition that all who had the honour of a meeting with the monarch were expected to walk discreetly backwards when leaving the Sovereign's presence has been dropped for health and safety reasons. These two senior members of the Royal Household are expected to walk backwards leaving the room when they have either been summoned to see the Queen personally or they are introducing others – such as senior foreign diplomats – for audiences with the Queen.