At the moment that Queen Elizabeth II died, the throne passed immediately and without ceremony to the longest-serving heir, Charles, the former Prince of Wales.
The 73-year-old’s first decision as the new king was to choose from one of his four names – Charles Philip Arthur George – and he has decided to be called King Charles III.
With a long history of triumphs and scandals, King Charles III still has a number of steps to cross before being crowned the King.
There is also a new title for Charles' wife, Camilla, who becomes the Queen Consort – a term used for the spouse of the monarch.
What Is the Protocol?
It is expected that Charles will be officially proclaimed King on Saturday, at the St James Palace in London, in front of a ceremonial body known as the Accession Council.
The Accession Council is made up of members of the Privy Council – a group of senior MPs, past and present, and peers – as well as some senior civil servants, Commonwealth high commissioners, and the Lord Mayor of London, BBC reported.
While over 700 people are entitled to attend in theory, the actual number is likely to be fewer. For instance, at the last Accession Council in 1952, about 200 attendees were present.
At the council’s meeting, Lord President of the Privy Council, MP Penny Mordaunt, will announce Queen Elizabeth’s death and then a proclamation will be read aloud.
While the proclamation has traditionally been a series of prayers and pledges, lauding the previous monarch and pledging support for the new one, the wording can change as a sign of a new era.
It will then be signed by a number of senior figures including the prime minister, the archbishop of Canterbury, and the lord chancellor.
The King's First Declaration
In the second meeting of the King with the Accession Council and the Privy Council, King Charles III will make a declaration in line with a tradition dating from the early 18th century and make an oath to preserve the Church of Scotland.
A public proclamation will then be made from a balcony above the Friary Court in the St James Palace declaring Charles as the new King.
An official known as the Garter King of Arms will make the proclamation saying, "God save the King.”
This will be followed by the national anthem "God Save the King", instead of the anthem being played since 1952 which was “God Save the Queen.”
Gun salutes will be fired in Hyde Park, the Tower of London, and from naval ships, and the proclamation announcing Charles as the King will be read in in Edinburgh, Cardiff, and Belfast, BBC reported.
The Coronation
While the new king will be proclaimed on Saturday, the crowning will come after lengthy preparations are done for the new monarch’s reign and will be held in Westminster Abbey.
Queen Elizabeth II had succeeded to the throne in February 1952, but was not crowned until June 1953.
William the Conqueror was the first monarch to be crowned there 900 years ago and Charles will be the 40th.
The coronation, an Anglican religious service, will be carried out by the Archbishop of Canterbury, who will place St Edward's Crown, dating from 1661, on Charles's head.
Weighing 2.23kg, the gold crown is the centrepiece of the Crown Jewels at the Tower of London, and is only worn by the monarch at the moment of coronation itself.
During the elaborate ceremony, Charles will receive the orb and sceptre as symbols of his new role and the Archbishop of Canterbury will place the solid gold crown on his head.
Since the coronation is a state occasion, the government will be the one to decide the guest list.
With the gold crown, also comes the responsibility of being the head of the Commonwealth, an association of 56 independent countries and 2.4 billion people.
Further, for 14 of these countries, the King is the head of state. These countries are Australia, Antigua and Barbuda, the Bahamas, Belize, Canada, Grenada, Jamaica, Papua New Guinea, St Christopher and Nevis, St Lucia, St Vincent and the Grenadines, New Zealand, Solomon Islands, and Tuvalu.
(With inputs from BBC.)