LUXEMBOURG (AP) — Grand Duke Guillaume swore an oath to ascend to the throne of Luxembourg on Friday in a traditional ceremony attended by royals and European heads of state. Church bells rang out just before hundreds crowded outside the Grand Palace began chanting “Guillaume, Guillaume!” as the new grand duke walked onto a balcony to greet his new subjects. Grand Duke Guillaume, 43, wearing an olive-green military uniform with a yellow sash, was flanked by the royal family, including his wife, Grand Duchess Stéphanie, in a sky-blue gown. From left, Belgium's Queen Mathilde, Luxembourg's Grand Duchess Maria Teresa, Belgium's King Philippe, Luxembourg's Grand Duke Henri and Belgium's Princess Elisabeth pose during arrivals for the abdication and enthronement ceremony of the Grand Duke of Luxembourg at the Grand Ducal Palace in Luxembourg, Friday, Oct. 3, 2025. Nefeni Neocleousk, 18, wore a Luxembourgish flag across her shoulders and wished the grand duke well in the Luxembourgish language.