Grand Duke Guillaume of Luxembourg celebrates his 44th birthday on 11th November. Pictured, the leader with his wife, Grand Duchess Stephanie, during the celebrations marking his accession last month
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It has been an extraordinary year for Grand Duke Guillaume of Luxembourg, who acceded to the throne in October following the abdication of his father, Grand Duke Henri.
The occasion was marked by a weekend of celebrations, with foreign royals including King Willem-Alexander, Queen Maxima and Princess Catharina-Amalia of the Netherlands, and King Philippe, Queen Mathilde and Princess Elisabeth of the Belgium, among the dignitaries invited to witness the historic changing of power.
There was a triumphant balcony appearance, glittering banquet and a number of walkabouts that gave Grand Duke Guillaume of Luxembourg the opportunity to meet the people of the principality in his new capacity as ruler.
Prince Guillaume – pictured here on his wedding to Princess Stéphanie, will be named Lieutenant Representative of Luxembourg, marking the beginning of a transition of power from his father, Grand Prince Henri
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Now, Grand Duke Guillaume has even more to celebrate. For 11th November 2025 marks the leader’s 44th birthday.
So who is the new ruler of Luxembourg? Grand Duke Guillaume of Luxembourg was born 11 November 1981 at the Grand Duchess Charlotte Maternity Hospital in Luxembourg City. The eldest child of Grand Duke Henri – then heir apparent – and the Cuban-born Grand Duchess Maria Theresa, Guillaume enjoyed an education fit for a prince. He joined a to roll call of scions to come-of-age amid the chalets of the Institut Le Rosey – a Swiss boarding school with campuses in Gstaad and on the shores of Lake Geneva that has seen Rothschilds and Rockefellers walk its halls alongside the Duke of Kent, Crown Princess Marie-Chantal of Greece, and Prince Dasho Ugyen Jigme Wangchuck of Bhutan.
Like his father, Guillaume then moved to Britain to undergo another royal ritual: training at Sandhurst. He would go on to become a Colonel in the Luxembourg army. The Prince stayed in England, enrolling at Durham University and Brunel University in London. One of the most educated royals in Europe, Guillaume has studied at countless illustrious institutions, reading philosophy and anthropology at Institut Philanthropos in Fribourg, letters and political science at the Institut Albert-le-Grand in Angers, and undergoing postgraduate training at the Royal College of Defence Studies in London. He may be nervous about getting to grips with the minutiae of international diplomacy, but Guillaume is surely among the most qualified rulers throughout any continent.