By Sarah Motherwell for the ABC*
Camilla will be formally known as Queen Consort now that her husband Charles is King.
For years it was believed she would become princess consort - which would have been a first in British history. But in February 2022 the late Queen Elizabeth II gave her backing for her son's wife to adopt the queen consort title.
Here's what the title means for the royal family.
What does queen consort mean?
A queen consort is the female partner, spouse or companion to the King.
The consort is not a formal role, and is symbolic of the support the person gives the monarch.
It is different to the queen regnant, who is the ruler in their own right, like Queen Elizabeth II.
Before her, the previous queen regnant was Queen Victoria, whose husband Prince Albert was prince consort.
Historically, male spouses to the queen regnant have taken on the title prince consort rather than king consort.
However, the proposed title of princess consort for Camilla was "a bit of a compromise", royal family historian Dr Cindy McCreery explains.
"Princess consort was a compromise that arose because of the sense of grief and anger, notably at the death of Princess Diana," she told the ABC.
"But also at the resentment in many quarters towards Camilla for what many people felt was the improper relationship that Charles and Camilla had during the time that Charles was still married to Diana."
Charles had a long-running intimate relationship with Camilla before and during his marriage to Diana Spencer in 1981.
At the time, Camilla was also married to army officer Andrew Parker Bowles.
Charles and Diana divorced in 1996, and Diana retained the title Princess of Wales.
A year later, Diana died in a car crash in Paris, aged 36.
Camilla and Charles married in a civil ceremony at Guildhall in Windsor on April 9, 2005.
The Queen, as head of the Anglican Church, did not attend the ceremony, but did host and attend the reception at Windsor Castle afterwards.
"We saw a situation arise where, [as] a kind of compromise position, Queen Elizabeth suggested that Camilla would be not queen but princess," Dr McCreery said.
"That's a very unusual situation in the normal course of events - the wife of a king in Britain is known as queen consort."
In February 2022, the Queen said in a special Platinum Jubilee message that it was now her "sincere wish" that Camilla be known as queen consort when Charles came to the throne.
Why was Prince Philip not called king consort?
Prince Philip was the longest-serving British consort in history and held the title prince consort for 69 years.
Dr McCreery said it was tradition for the male spouse of a reigning queen to be known as prince consort to "bolster the authority of the woman".
Britain had one dual monarchy in the late 17th century when King William and Queen Mary ruled together after the abdication of her father, King James II.
"The British parliament asked William of Orange, who was related to the British dynasty but only remotely, and his wife Mary, who was James's eldest Protestant daughter, to become the new monarchs," Dr McCreery said.
"It was important Mary was known and recognised as queen because she was the heir.
"This is quite an important but really unusual event where it's really important for the sake of the stability of the crown that you had a king and queen ruling together.
"But other than that, when there's been a queen ruling, it's really important that her husband is not confused in people's minds as somehow a king, and therefore he takes a title of prince consort."
Will we be calling Camilla queen or queen consort?
Dr McCreery says while queen consort is the formal title, it is not used in general practice.
"For example with Queen Elizabeth II's parents, her father was King George VI, her mother was queen consort," she said.
"But in practice, she was known was Queen Elizabeth (her name was also Elizabeth).
"It might be the formal term, but we don't in practice say the king and queen consort. We say king and queen."
- ABC