Tradition and protocol dictate every aspect of royal life -- and death. From the moment Queen Elizabeth ascended the throne, Philip Murphy, a professor of British and Commonwealth history at the University of London, told The New York Times that "Whitehall started the planning process about what would happen when [the queen] died."
This plan -- Operation London Bridge -- accounted for everything from the immediate changing of the national anthem back to "God Save the King" to how many public statements King Charles III must make now that he's ascended, per The New York Times. According to Vanity Fair, Charles will also be embarking on a train tour of the United Kingdom to "mourn with various communities." His first stop is expected to be Edinburgh, to visit Scottish Parliament and St. Giles Cathedral.
Operation London Bridge's plans also included how long a period of mourning would be observed and performed by the royal family. From the day of her death through the queen's funeral, which will take place 10 days after her passing, Express reports the royal family must wear black. Protocol is so strict that, according to Tatler, all royal family members are expected to travel with black outfits -- just in case.
Buckingham Palace staff must also observe mourning through wearing black three-and-a-quarter-inch wide bands on their left arms, per Express.
According to Matthew Storey, curator at Historic Royal Palaces, Queen Victoria "set a standard" for mourning protocol when she wore black for 40 days following the death of Prince Albert (via The Telegraph).
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