The minute Queen Elizabeth passed away yesterday was the minute Prince Charles became King.
He'll now reign as King Charles III, with Downing Street swiftly confirming the title he will inherit.
But despite Charles being his Christian name, he could have chosen any of his four monikers to rule under - Charles Phillip Arthur George.
The Times reported in 2005 how the then Prince of Wales considered taking on the title George VII as a heartfelt tribute to his grandfather, the Queen's dad who became a beloved King following the abdication of his brother, Edward.
Other reasons for the possible change in name, however, may have been that 'King Charles' is considered somewhat 'jinxed' among the upper echelons.
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The two Charleses to precede our now King both died relatively young - with the first executed in what is the only execution of a British monarch in history.
Charles I was beheaded at Whitehall in 1649 after being convicted of treason the year before. With Charles dead, the monarchy was abolished and his son and would-be king Charles exiled from the country.
England would not have another king for 11 years, when Charles II eventually took the throne.
A somewhat controversial king, Charles II was known for his many mistresses and saw the country through a tumultuous period of change and mass death, including the Great Plague and the Great Fire of London.
He died 25 years after being crowned at the age of 54, after falling into apoplectic fits.
Our now King will be the first Charles on the throne in almost 400 years.
Trusted friends of the then Prince told The Times in 2005 that the name "is tinged with so much sadness".
"They (the Royal Family) will decide at the time, but he has talked about George,” one friend claimed at the time.
This story, however, was later rebuffed by another friend, who correctly predicted Charles would indeed keep his name.
“Anyone who knows the Prince of Wales knows he does not sit around talking to his chums, discussing what he wants to be called,” the source told The Guardian.
"Inasmuch as officials have discussed it with him at accession planning meetings the thinking was that he would remain, Charles,” they added.
Charles III will now lead the country in a state of mourning for his mother for 10 days, and will take on his first duty by addressing the nation in a speech tonight.
Dates for the Queen's funeral and Charles' coronation will be confirmed in the coming days and weeks.
You can leave your tributes to Queen Elizabeth II here
