His Royal Highness Grand Duke Jean of Luxembourg was born on the 5th of January 1921 at the Chateau Berg in Luxembourg as the eldest son of Her Royal Highness Charlotte, Grand Duchess of Luxembourg and Prince Felix of Luxembourg, Prince de Bourbon-Parma. After him were born Elisabeth, Marie-Adelaide, Marie-Gabrielle and Charles. 
              His education began with a private teacher at the Chateau Berg.  He learned the national language, Letzeburgish, then French, English and German. He received his secondary education at Athenee        (Luxembourg) and Ampleforth College (Great Britain). When German troops invaded the Grand Duchy on the 10th of May 1940, Prince Jean left Luxembourg with the Grand Ducal family. They found refuge first   in France and Portugal before leaving for the United States and then settled in Canada's Quebec City. 
             Prince Jean went to the Ecole des Sciences Sociales at the Universite Laval in Quebec City. In November 1942 he joined the British Army as a volunteer in the Irish Guards and attained the rank of lieutenant in 1943 and of captain in 1944. 
             In 1943-44 he studied at the Sandhurst Military Academy in Great Britain. On the 11th of June 1944 he crossed the Channel, landing near Bayeux. He served in Normandy as Liaison Officer to the 3rd Bn Irish  Guards at HQ, 32nd Brigade which was a part of the Guards Armoured Division. On the 10th of September 1944, he joined his father, Prince Felix, and the 1st Allied troops that liberated Luxembourg. 
             From 1945 to 1964 he was Colonel and Assistant inspector General of the Luxembourg Army. From 1951 till 1961 he was a Member of the State Council. In 1953 he married Princess Josephine Charlotte of 
Belgium and they became the parents of five children: Marie-Astrid, Henri, Jean, Margaretha and Guillaume. 
             From 1961 till 1964 he was Lieutenant-Representant of HRH Grand Duchess Charlotte and, when she abdicated, became Grand Duke of Luxembourg. On 7 October 2000, in turn he abdicated in favour of his son, Henri. 

Source: Philippe Bernier Arcand, Leo van de Pas