The Prince of Wales became king, having ascended the throne soon after the death of his mother, the queen.
Charles – the nation’s longest-lived heir apparent, having been this way since he was three – is now fulfilling his royal destiny and reigns as monarch.
Despite his grief, duty demands the new king at the start of this new royal era, asking him to immediately turn his hand to matters of state as ruler and lead the nation in mourning.
Charles – now called His Majesty rather than His Royal Highness – is expected to deliver a televised speech in honor of his beloved mother.
In the coming days he will meet the Prime Minister, confirm funeral plans and tour the UK with his wife, Camilla, who is now the queen consort and has the title of queen.
Charles automatically became king thanks to the Charter of Rights of the seventeenth century (1689) and the Act of Settlement (1701).
But there must be a formal proclamation of him as the new monarch in an Accession Council at St James’s Palace in London as soon as possible.
The council is generally convened the day after the death of a sovereign.
It consists of two parts.
First, the Private Council – to which 200 of the more than 700 private councilors will be summoned – meets without the sovereign to proclaim the new monarch and organize affairs related to the proclamation.
Then, secondly, the new king holds his first Private Council.
Charles will make a personal statement about the Queen and then take an oath to preserve the Church of Scotland, because in Scotland there is a division of power between Church and State.
Subsequently, the first public proclamation of the new sovereign is read in the open from the balcony of the convent court at St James’s Palace by the King of Arms of the Garter in the presence of the Count Marshal and two Serjeants at Arms of the sovereign.
In the midst of a grand ceremony, trumpeters usually play a fanfare from the balcony and gunshots are fired in Hyde Park and the Tower of London.
The proclamation will then be read at the Royal Exchange in the City of London.
It is also read publicly at some point in other cities including Edinburgh, Cardiff and Belfast and usually in Windsor and York, where traditionally the mayor drinks the new ruler’s health from a golden goblet.
Charles has become known for his commitment to royal duty, environmental campaigning, and his charitable work over the years.
But his personal problems also spiced up his long wait to become monarch, most notably the breakup of his marriage to the Princess of Wales and his relationship with Camilla Parker Bowles, now his wife and queen.
Camilla was approved to be known as the queen by her mother-in-law 17 years after she married the prince in 2005.
At the time of her wedding, the attendants insisted that Camilla did not want to be the queen and would not be known as such.
As the UK’s head of state, Charles will now take on constitutional and representative duties that have developed over more than 1,000 years of history.
He is now chief of the armed forces and head of the Church of England, and also monarch of numerous Commonwealth kingdoms.
The coronation of the new king is likely not to happen for many months and will involve very detailed planning.
Codenamed Operation Golden Orb, Westminster Abbey service is expected to be shorter, cheaper and more inclusive than multi-religious Britain.
But the coronation remains a deeply religious Anglican occasion.
The queen ascended the throne in February 1952, but her coronation took place only 16 months later, in June 1953.
Unlike the queen, who became sovereign at 20, Charles spent more than 70 years – most of his life – as a waiting king, becoming the longest-serving heir in British history.