Prince Guillaume is the new Grand Duke of Luxembourg. The royal succeeded his father, Grand Duke Henri, on Oct. 3, 2025. Henri, who had been the head of state since 2000, announced in his 2024 Christmas speech that he would be abdicating in favor of his son days before the 25th anniversary of his own accession.
Guillaume has said that he sees his role "as Head of State as that of a unifying figure for all who consider Luxembourg their home." "I intend to defend our independence, preserve our traditions and wisely embrace the opportunities that will shape our future," he said. "Guided by the values of integrity, compassion and service, I am committed to strengthening social cohesion, safeguarding our democratic stability and supporting a sustainable, innovative and prosperous economy. Together with the citizens of Luxembourg, we will cross the bridge to a future that honours our past while shaping a vibrant and inclusive tomorrow."
1. He was born on Nov. 11, 1981 in Luxembourg.
2. He is Grand Duke Henri and Grand Duchess Maria Teresa's eldest child.
3. He has four younger siblings: Prince Félix, Prince Louis, Princess Alexandra and Prince Sébastien.
4. He became the Hereditary Grand Duke of Luxembourg after his father's accession to the throne on Oct. 7, 2000.
5. He married his wife, Grand Duchess Stéphanie, on October 20, 2012 at the Notre-Dame Cathedral of Luxembourg.
6. He and Stéphanie have two kids. They welcomed their first child, Prince Charles Jean Philippe Joseph Marie Guillaume, on May 10, 2020. Their second son, Prince François Henri Luis Marie Guillaume, was born on March 27, 2023.
7. He has been a member of the Scouts since he was a child, and in 2019, he became the Chief Scout of Luxembourg.
8. According to the Grand Ducal Court of Luxembourg's website, Guillaume "is passionate about playing the guitar."
9. He is a godparent to King Philippe and Queen Mathilde of Belgium's son Prince Emmanuel.
10. The royal is said to enjoy tennis, skiing, swimming and water sports.
11. He is fluent in five languages, Luxembourgish, French, German, English and Spanish, per the Grand Ducal Court.
12. His father appointed him Lieutenant-Représentant in October 2024.
13. He took the oath of office before the Chamber of Deputies on Oct. 3, 2025. Per the Grand Ducal Court's website, "The Grand Duke plays an important role in the functioning of the Luxembourg state. In his official capacity, he represents the State both domestically and internationally."
14. His son Prince Charles is now first in the line of succession to the throne.