|Prince Sigismund of Prussia|
|Born||27 November 1896|
Kiel, Schleswig-Holstein, German Empire
|Died||14 November 1978 (aged 81)|
Puntarenas, Costa Rica
|Burial||21 November 1978|
Esparza, Costa Rica
Princess Charlotte of Saxe-Altenburg
|Father||Prince Henry of Prussia|
|Mother||Princess Irene of Hesse and by Rhine|
|House of Hohenzollern|
Prince William Victor Charles Augustus Henry Sigismund of Prussia (German: Wilhelm Viktor Karl August Heinrich Sigismund; 27 November 1896 at Kiel – 14 November 1978 at Esparza, Costa Rica), was the second son of Prince Henry of Prussia and Princess Irene of Hesse and by Rhine. He was the nephew of Kaiser Wilhelm II and Tsarina Alexandra of Russia. As the great-grandson of Queen Victoria through both his parents, he was the only one of three brothers who did not have the hemophilia common among her descendants.
Marriage and issue
- Barbara Irene Adelheid Viktoria Elisabeth Bathildis (2 August 1920 – 31 May 1994), married Duke Christian Louis of Mecklenburg
- Alfred Friedrich Ernst Heinrich Conrad (17 August 1924 – 3 June 2013)
Prior to emigrating from Europe to Central America, he served as a marine officer.
In 1927, Sigismund and his family resettled in Costa Rica  three years after his son Alfred (1924–2013) had been born in Guatemala.  He planned to engage in banana and coffee planting on land he owned there.
In 1957, Sigismund returned to Germany to meet with Anna Anderson whom he recognized as his cousin Grand Duchess Anastasia. During this visit he also met and acknowledged Marga Boodts who claimed to be Grand Duchess Olga Nikolaevna of Russia and Ceclava Czapska who claimed to be Grand Duchess Maria Nikolaevna. In 1972, he once again reaffirmed his belief when talking to BBC journalists Anthony Summers and Tom Mangold, who were writing the File on the Tsar.
Honours and awards
Prince Sigismund received the following awards:
- Order of the Black Eagle, Knight (Kingdom of Prussia)
- Order of the Red Eagle, Grand Cross with Crown (Kingdom of Prussia)
- Order of the Prussian Crown, Grand Cross (Kingdom of Prussia)
- Royal House Order of Hohenzollern, Grand Commander (Kingdom of Prussia)
- Princely House Order of Hohenzollern, Cross of Honour 1st Class (House of Hohenzollern-Sigmaringen)
|Ancestors of Prince Sigismund of Prussia (1896–1978)|
- Eilers, Marlene. Queen Victoria's Descendants. Rosvall Royal Books, Falkoping, Sweden, 1997. pp. 27-28, 131, 173. ISBN 91-630-5964-9
- de Badts de Cugnac, Chantal. Coutant de Saisseval, Guy. Le Petit Gotha. Nouvelle Imprimerie Laballery. Paris. 2002. pp. 78, 91-93 (French) ISBN 2-9507974-3-1
- "preussen.de". Archived from the original on 2014-10-06. Retrieved 2014-06-26.
- "Prussian Prince Moves to Costa Rica", The New York Times, Colon, 22 December 1927
- "Alfred Friedrich Ernst Heinrich Conrad Prince of Prussia" thepeerage.com (April 8, 2016); retrieved April 19, 2021
- Handbuch über den Königlich Preußischen Hof und Staat (1918), Genealogy p.3