The Prince of Wales marked a profoundly personal milestone this week, stepping out for a formal royal engagement on what would have been his mother's 65th birthday.

Prince William joined King Charles, Queen Camilla, and other senior members of the Royal Family for the annual Order of the Thistle service at St. Giles' Cathedral in Edinburgh. The ceremony, which took place on July 1, carried significant emotional weight as it coincided with the birthday of the late Princess Diana.

Known as the Duke of Rothesay when in Scotland, William arrived at the historic cathedral with his uncle, Prince Edward. The 44-year-old heir to the throne donned the Order's traditional deep green velvet robe and a black hat adorned with distinctive white ostrich feathers for the occasion. The King and Queen were welcomed with a Royal Salute from The King's Body Guard for Scotland and the playing of the national anthem.

Scotland’s Highest Order of Chivalry

The Order of the Thistle is recognized as Scotland's greatest order of chivalry and the highest honor in the nation. The prestigious order limits its membership to just 16 Knights and Ladies at any given time, recognizing individuals who have made significant contributions to national life.

The order was founded in 1687 and remains one of the world's oldest and most exclusive orders of chivalry. King Charles serves as Sovereign of the Order, with Queen Camilla, Princess Anne, Prince Edward, and Prince William all counted among its members. Queen Elizabeth II made the historic decision to open the order to women in 1987.

The service is a key fixture of Royal Week in Scotland, which began with the King participating in the Ceremony of the Keys at the Palace of Holyroodhouse. The annual event shares similarities with the Order of the Garter ceremony held at Windsor Castle each June.

Continuing Diana’s Legacy Through Action

The poignant timing of the engagement comes as William continues to champion causes inspired by his mother's humanitarian work. The day before the Edinburgh ceremony, the Prince marked a significant milestone for his Homewards initiative, a five-year project aimed at tackling homelessness across the United Kingdom.

William spent part of June 30 in Aberdeen, one of the flagship locations for the Homewards project where new initiatives are being piloted to combat homelessness. This commitment to helping the unhoused reflects the early lessons Diana imparted to her sons. The Princess of Wales introduced both William and Prince Harry to homeless shelters and charities when they were young, instilling in them a deep understanding of social issues.

William has embraced this legacy in his own way, even introducing his eldest son, Prince George, to the work of Homewards during Christmas 2025. The Prince of Wales has also been spotted selling magazines on behalf of homeless individuals, continuing his hands-on approach to the cause.

The back-to-back engagements in Scotland demonstrate how William balances formal royal duties with his commitment to carrying forward his mother's compassionate legacy on a day of deep personal significance.