Mariano Hugo, Prince of Windisch-Graetz

Windisch-Graetz was born at Trieste[1] as the elder son of Maximilian Antonius, Prince zu Windisch-Graetz and Maria Luisa (Marlise) Serra di Gerace.[1] His mother was the legitimatised daughter of Gian Battista Serra, 12th Principe di Gerace by Donna Maria Grazia Carafa d'Andria.[2]

Windisch-Graetz was educated firstly in Rome at the school of the De La Salle Brothers. In 1975 he graduated from University College of Buckingham with a degree in Economics and Political Science.[4]

When his father died in 1976, Windisch-Graetz succeeded as head of a cadet branch of the House of Windisch-Graetz,[1][5] a mediatised house whose members historically bore the style of Serene Highness.[1]

On 11 February 1990 in Salzburg, Austria, Windisch-Graetz married Sophie Habsburg, daughter of Archduke Ferdinand of Austria and Countess Helene zu Törring-Jettenbach,[1][5] daughter of Princess Elizabeth of Greece and Denmark.

The couple have had three children:

• Prince Maximilian Hugo
• Prince Alexis Ferdinand (who died at Sant'Angelo d'Alife in a car accident in 2010),[6]
• Princess Larissa Maria Grazia Helen Leontina Maria Luisa.[1]

Windisch-Graetz and his family reside in Italy when he is not abroad on diplomatic appointment, maintaining a home in Rome and Il Palazzo in Sant'Angelo d'Alife.[1]

The business activities of Windisch-Graetz include the food production industry, notably biscuits and mozzarella cheese, and entrepreneurial finance.[2] In the early 1990s, he was a major shareholder in the Banco di Napoli and a holding company, Sogesco, of which he owned 82%, was capitalised at 10 billion lire.[7]

On 19 December 1987, Pope John Paul II appointed Windisch-Graetz a Gentleman of His Holiness,[8] a role which entails meeting visiting heads of state and ambassadors and escorting them to meet the pope.[9] He is also a Knight of Honour and Devotion in Obedience of the Sovereign Military Order of Malta.[1]

In 2003, Windisch-Graetz was appointed Ambassador of the Sovereign Military Order of Malta to the Republic of Slovakia;[10] this appointment was renewed in 2006, until December 2009. In March 2009, he was appointed Ambassador of the Sovereign Military Order of Malta to the Republic of Slovenia.[11]

Mariano Hugo Prince of Windisch-Graetz (in the Vatican, 2019)

•  SMOM:
  • Knight of Honour and Devotion in Obedience of the Sovereign Military Order of Malta[1]
  • Grand Cross of the Order pro merito Melitensi
•   Holy See: Knight Grand Officer of the Order of the Holy Sepulchre
•  Morocco: Grand Officer of the Order of Ouissam Alaouite
• House of Bourbon-Two Sicilies: Knight of Justice of the Sacred Military Constantinian Order of Saint George[1]
• House of Braganza: Knight Grand Officer of the Order of Saint Michael of the Wing
• House of Habsburg: Knight of the Austrian Order of the Golden Fleece[1]
• House of Petrović-Njegoš: Knight Commander of the Order of Prince Danilo I
• House of Savoy:
  • Knight of the Collar of the Order of the Most Holy Annunciation[1][12]
  • Knight of Grand Cross of the Order of Saints Maurice and Lazarus[12][1]