The death of Queen Elizabeth II sets in motion a meticulously choreographed and coordinated procedure for which the palace, the government, the news media, the local authorities and the queen herself had long planned.

Amid the public mourning, the national grief and the lowering of flags will come a transition of power and national memorializing, known as Operation London Bridge, that will overtake the country’s agenda for days and play out potentially for months before the coronation of a new monarch.

"From the moment the queen became monarch, Whitehall started the planning process about what would happen when she died,” said Philip Murphy, a professor of British and Commonwealth history at the University of London.