Prince WilliamandKate Middleton’s titles as the Prince and Princess of Wales are now official.

Just one day after the Sept. 8, 2022, death ofQueen Elizabeth II,King Charles IIIgave his first speech as the United Kingdom’s monarch. In the televised broadcast, the new sovereignannouncedthat his son Prince William would be the new Prince of Wales and his daughter-in-law Kate would become the Princess of Wales.

However, the royal titles only became official this month, when the Letters Patent passed the Great Seal of the Realm on Feb. 13. The full notice from the Crown Office was printed inThe Gazetteon Friday.

Prince William and Kate Middleton at the BAFTAs 2023.Chris Jackson/Getty

LONDON, ENGLAND - FEBRUARY 19: Catherine, Princess of Wales and Prince William, Prince of Wales, attend the EE BAFTA Film Awards 2023 at The Royal Festival Hall on February 19, 2023 in London, England. The Prince of Wales, President of the British Academy of Film and Television Arts (BAFTA), and The Princess will attend the Awards ceremony before meeting category winners and EE Rising Star Award nominees. (Photo by Chris Jackson/Getty Images)

The announcement read in full: “In accordance with the direction of HIS MAJESTY THE KING Letters Patent have passed the Great Seal of the Realm, dated the 13th February 2023 for creating His Royal HighnessPrince WilliamArthur Philip Louis, Duke of Cornwall Rothesay and Cambridge, Earl of Carrick and Strathearn, Baron of Renfrew, Baron Carrickfergus, K.G., K.T., Lord of the Isles and Prince and Great Steward of Scotland, PRINCE OF WALES and EARL OF CHESTER.”

Queen Camilla, King Charles, Prince William and Kate Middleton.Chris Jackson/Getty

LONDON, ENGLAND - OCTOBER 01: (THE PHOTOGRAPH SHALL NOT BE USED AFTER FRIDAY, 14TH OCTOBER 2022 WITHOUT PRIOR PERMISSION FROM ROYAL COMMUNICATIONS. All terms of release must be adhered to. The photograph has been distributed with permission from Royal Communications. The photograph is being made available by way of licence on condition that the photograph shall be solely for news editorial use only, no charge should be made for the supply, release or publication of the photograph, there shall be no commercial use whatsoever of the photograph - including any use in merchandising, advertising or any other non-editorial use, the image must not be digitally enhanced, manipulated or modified in any manner or form and must include all of the individuals in the footage when published. THE PHOTOGRAPH SHALL NOT BE USED AFTER FRIDAY, OCTOBER 14, 2022.) In this handout image issued by Buckingham Palace, Camilla, Queen Consort, King Charles III, Prince William, Prince of Wales and Catherine, Princess of Wales pose for a photo ahead of their Majesties the King and the Queen Consort’s reception for Heads of State and Official Overseas Guests at Buckingham Palace on September 18, 2022 in London, England. (Photo by Chris Jackson/Getty Images)

William and Kate retained their Cambridge titles.

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Prince William and Kate Middleton.EDDIE MULHOLLAND/POOL/AFP via Getty

Britain’s Prince William, Prince of Wales (L) and Britain’s Catherine, Princess of Wales attend a pre-campaign launch event, hosted by The Royal Foundation Centre for Early Childhood, at BAFTA in central London on January 30, 2023.

The legal instruments known as letters patent are an open document from the monarch used to express the sovereign’s will, such as “to confer an office or create a new peerage,” according to theRoyal Collection Trust. Now, the letters patent makingPrince Williamthe Prince of Wales passed the Great Seal of the Realm.

Along with becoming the Prince of Wales, the letters patent also decreed that William is granted the title of Earl of Chester. That makes Kate the Countess of Chester.

July 1, 1969: Queen Elizabeth II crowns her son Charles, Prince of Wales, during his investiture ceremony at Caernarvon Castle.Hulton Archive/Getty

Prince Charles, queen elizabeth

Charles, now 74, was just 3 when his mother,Queen Elizabeth, acceded to the throne. He was not formally pronounced the Prince of Wales until he was 9, and theInvestiture of the Prince of Wales— when Charles was presented to the Welsh people as their prince — took place at Caernarfon Castle in 1969 when Charles was 20.

Such a ceremony is not expected to take place forPrince William, but he will likely play a role inKing Charles' coronationon May 6.

source: people.com