The son of reigning Prince Hans-Adam and dad of three was seventh in the line of succession

Brothers Prince Maximilian (l) and Constantin (r) Toast with Crown Prince Alois of Liechtenstein After a Ceremony Marking the Handing Over of the State Leadership Vaduz 15 August 2004 Prince Hans-adam Ii Von Und Zu Liechtenstein Handed Over His Powers to His Son Alois Today at a Garden Party For His Subjects
Prince Constantin of Liechtenstein in 2004. PHOTO: ARNO BALZARINI/EPA/SHUTTERSTOCK
The Princely House of Liechtenstein is mourning the sudden death of Prince Constantin at age 51.

The royal house announced the news in a statement on Wednesday and did not disclose a cause of death.

Prince Constantin is the youngest son of Prince Hans-Adam II, the current reigning prince of Lichtenstein, and was seventh in the line of succession to the throne. He is survived by his wife, Princess Marie, and their three children, Prince Moritz, 20, Princess Georgina, 18, and Prince Benedikt, 15.

“The Princely House regrets to announce that S.D. Prince Constantin of Liechtenstein died unexpectedly on December 5, 2023. Prince Constantin was the youngest son of Prince Hans-Adam II,” the Princely House said in a statement. “He leaves behind his wife, Princess Marie of Liechtenstein, née Countess Kálnoky of Kőröspatak, and his children Prince Moritz, Princess Georgina and Prince Benedikt.”

Brothers Prince Maximilian (l) and Constantin (r) Toast with Crown Prince Alois of Liechtenstein After a Ceremony Marking the Handing Over of the State Leadership Vaduz 15 August 2004 Prince Hans-adam Ii Von Und Zu Liechtenstein Handed Over His Powers to His Son Alois Today at a Garden Party For His Subjects
Brothers Prince Maximilian (l) and Constantin (r) Toast with Crown Prince Alois of Liechtenstein at an event in 2004. ARNO BALZARINI/EPA/SHUTTERSTOCK
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Sharing a line about his professional background, courtiers continued, “Prince Constantin was chairman of the supervisory board of Liechtenstein Group AG and a member of Board of Directors of Liechtenstein Group Holding AG.”

Fan blog LiechtensteinRoyal posted a tribute on X, sharing the same photo that Liechtensteiner Vaterland newspaper published with Constantin’s obituary. According to the outlet, Prince Constantin was born in St. Gallen in March 1972 and graduated from the Liechtenstein High School before studying law in Salzburg.

The Liechtenstein government was deeply saddened to note the news of the death of SD Prince Constantin of Liechtenstein. As the Princely House announced today, the youngest son of SD Prince Hans-Adam II of Liechtenstein died unexpectedly yesterday. 
+ pic.twitter.com/RK2XqOJVnu

— LiechtensteinRoyal (@RFLiechtenstein) December 6, 2023

Vaterland said that Constantin had served as general director and chairman of the board of the Prince Liechtenstein Foundation for 11 years and noted that the group “holds almost all of the royal family’s assets, such as one of the largest private art collections in the world, the LGT Group, a museum, the Vaduz Hofkellerei [one of the royal family’s wine cellars] and various properties.”

The Lichtenstein Group explains that its companies are held by the Foundation Prince Liechtenstein, and the organization released a statement following Constantin’s death.

“His death comes as a terrible shock to all those who knew him, and the Liechtenstein Group is in deep mourning,” the message said. “Our thoughts and prayers go out to his widow Princess Marie von und zu Liechtenstein, and their children Moritz, Georgina, and Benedikt.”

Prince Constantin with Princess Marie
Prince Constantin and Princess Marie attend a wedding in 2005. FRANK ROLLITZ/SHUTTERSTOCK
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Liechtenstein is a German-speaking principality double landlocked by Switzerland and Austria. Roughly the size of Washington, D.C., it is one of the smallest countries in the world with a population of about 40,000, according to the American Embassy of the Principality of Liechtenstein.

As a constitutional hereditary monarchy, the reigning prince of the Princely House of Liechtenstein and a democratically elected parliament share political power through a system of checks and balances, per the Princely House of Liechtenstein.

Constantin’s father Prince Hans-Adam II is the current reigning prince of Liechtenstein, and Constantin’s elder brother Hereditary Prince Alois is next in the line of succession.