Prince William wore velvet robes and ostrich plume in his hat for the annual celebration of the Order of the Garter, one of the oldest orders of knighthood in the U.K.

By Stephanie Petit and Simon Perry
June 17, 2019 10:08 AM

Kate Middleton watched proudly as husband Prince William paraded down the walkway of Windsor Castle on Monday for a very royal occasion.

After skipping last year’s ceremony while on maternity leave, Kate was all smiles while William wore the velvet robes and high ostrich plume in his hat for the annual celebration of the Order of the Garter, one of the oldest and most senior order of knighthood in the U.K. The royal mom, 37, wore black and white for the occasion, pairing a Catherine Walker "Liza" coat with a Lock & Co. hat.

The parade to St. George’s Chapel — which recently hosted the royal weddings of Prince Harry to Meghan Markle and Princess Eugenie to Jack Brooksbank — followed a lunch in the Waterloo Chamber of the castle. The service was followed by carriage rides out of the chapel and up the hill back to the state apartments.

Kate stood at the Galilee porch of the chapel as the parade of Knights passed by.

Kate Middleton
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Prince William and Prince Charles
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William was made a Knight in what is the most senior order of chivalry in the U.K. in 2008. Kate memorably attended the ceremony that year, three years before they married.

Prince Harry and Kate Middleton at Order of Garter ceremony 2008
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Kate Middleton and Prince William at Order of Garter ceremony 2014
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Hosted by his grandmother Queen Elizabeth, the Order of the Garter ceremony is one of the grand high points in the royal calendar. And this year, it saw two royal couples from Spain and the Netherlands join the occasion.

Queen Elizabeth
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King Felipe of Spain and King Willem-Alexander were at Garter Day, as the Queen installed them as Supernumerary, or “Stranger,” Knights of the Garter during the service at St. George’s Chapel.

Earlier in the day, during a private Investiture in the Garter Throne Room, Windsor Castle, former athlete Lady Mary Peters, and the Marquess of Salisbury, were invested with the Order’s insignia by the Queen.

King Felipe, Queen Elizabeth and Queen Letizia
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King Willem-Alexander, Queen Elizabeth and Queen Maxima
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Felipe, who attended with wife Queen Letizia, had been appointed during the Spanish State Visit in July 2017, and King Willem-Alexander, whose wife Queen Maxima was by his side, received his appointment during his State Visit in October 2018.

King Willem-Alexander joins his mother and former monarch, Princess Beatrix, who was appointed to the order in 1989, while King Felipe’s father, Juan Carlos, was also named a “supernumerary” member. King Harald V of Norway and Emperor Emeritus Akihito of Japan have also been given the honor.

King Willem-Alexander, Queen Maxima and Kate Middleton
Sophie Countess of Wessex, Queen Letizia of Spain, Camilla Duchess of Cornwall, Queen Maxima of the Netherlands and Kate Middleton
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Queen Letizia, Camilla Duchess of Cornwall and Kate Middleton
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The Order of the Garter was founded by Edward III in 1348 and is the most senior order of knighthood in the British honors system. The number of companions is limited to 24, although supernumerary members do not count towards this total.

Queen Letizia and Kate Middleton
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Queen Maxima
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The Order includes the Queen, who is Sovereign of the Garter, several senior members of the royal family, and 24 knights chosen in recognition of their work. Knights of the Garter are chosen personally by the monarch to honor those who have held public office, contributed to national life or personally served the monarch.