Jean later volunteered to join the British army's Irish Guards in 1942, and after graduating from the Royal Military Academy Sandhurst, received his commission in 1943.

Jean was born on 5 January 1921[1] at Berg Castle in central Luxembourg, the first child of Grand Duchess Charlotte and of Prince Félix.

[3] Prince Jean was raised with his five siblings, and grew up primarily at his parents' residence, Berg Castle, in the town of Colmar-Berg.

At first, they sought refuge in Paris, before fleeing France only weeks later, after receiving transit visas to Portugal from the Portuguese consul Aristides de Sousa Mendes, in June 1940.

After travelling through Coimbra and Lisbon, the family first stayed in Cascais, in Casa de Santa Maria, owned by Manuel Espírito Santo, who was then the honorary consul for Luxembourg in Portugal.

[4] The grand duchess travelled from Portugal to London, where a government in exile was set up, before joining her family in North America.

[4] After receiving officer training at the Royal Military College at Sandhurst,[4] Jean was commissioned as a lieutenant on 30 July 1943,[9] before being promoted to captain in 1944.

[10] From 1984 until his abdication, he served as Colonel of the Regiment of the Irish Guards,[4] often riding in uniform behind Queen Elizabeth II during the Trooping the Colour.

There had been speculation that the marriage was arranged to improve relations between Luxembourg and Belgium but it soon became apparent that a love match was blooming between two longtime friends.

Indeed, during his reign Grand Duke Jean saw Luxembourg transformed from a minor industrial contributor into an international financial centre.

The degree of stability in the country's politics, economy and social life was without precedent, thanks in part to the influence of the Grand Duke and his wife.

[22] Surrounded by his family, Grand Duke Jean died at 00.25 CEST on 23 April 2019 at the age of 98 after he had been hospitalized for a pulmonary infection.

[27] Jean-Claude Juncker, president of the European Commission and former Prime Minister of Luxembourg, described Jean's death as "a great loss for the Grand Duchy and for Europe".

"[26] Luxembourg's Prime Minister, Xavier Bettel, alluded to his service in the Second World War: "Grand Duke Jean fought for our freedom, for our independence and for the unity of our country and we will always be grateful.

[30] The president of the International Olympic Committee Thomas Bach paid tribute to Grand Duke Jean who had joined the IOC in 1946 and had been an honorary member since 1998.

[35] The Arrêté Grand-Ducal (Grand Ducal decree) of 21 September 1995 established that the title of Prince/Princesse de Luxembourg is reserved for the children of the sovereign and the heir to the throne.

The line can be traced back more than 1,200 years from Robert of Hesbaye to the present day, through Kings of France & Navarre, Spain and Two-Sicilies, Dukes of Parma and Grand-Dukes of Luxembourg, Princes of Orléans and Emperors of Brazil.