|Date of birth||Berlin, Germany|
|Date of death||Jul 18, 1920 Potsdam, Brandenburg, Germany|
|Awards||Order of the Black Eagle, Knight Grand Cross of the Royal Victorian Order|
Prince Joachim Franz Humbert of Prussia (17 December 1890 – 18 July 1920) was the youngest son of Wilhelm II, German Emperor, by his first wife, Augusta Victoria of Schleswig-Holstein.
Candidate for thrones
While they were not in favour of a monarchy per se, Pearse and Plunkett thought that if the rising were successful and Germany won the First World War, an independent Ireland would be a monarchy with a German prince as king, like Romania and Bulgaria before it.
The fact that Joachim did not speak English was also considered an advantage, as he might be more disposed to learning and promoting the use of the Irish language.
After Georgia's declaration of independence following the Russian Revolution of 1917, Joachim was briefly considered by the German representative Friedrich Werner von der Schulenburg and Georgian royalists as a candidate to the Georgian throne.
Prince Joachim married Princess Marie-Auguste of Anhalt (10 June 1898 – 22 May 1983), the daughter of Eduard, Duke of Anhalt and his wife Princess Luise of Saxe-Altenburg (daughter of Prince Moritz of Saxe-Altenburg), on 11 March 1916. The couple had one son, the Prince Karl Franz Josef Wilhelm Friedrich Eduard Paul (Potsdam, 15 December 1916 – Arica, Chile 22 Jan 1975).
After his father's abdication, Joachim was unable to accept his new status as a commoner and fell into a deep depression, finally committing suicide by gunshot on 18 July 1920 in Potsdam. One source reports that he had been in financial straits and suffered from "great mental depression". His own brother Prince Eitel Friedrich of Prussia commented that he suffered from "a fit of excessive dementia". Before his death, the couple had recently divorced. The direct causes are not really known to the public, only that there had been no previous report of marital troubles before the divorce was announced. Regardless of the reasons, this event may have also contributed to his depression.
Children and grandchildren
The only issue of the marriage of Prince Joachim and Princess Marie-Auguste was their son, Prince Karl Franz Josef Wilhelm Friedrich Eduard of Prussia (15 December 1916 Potsdam, Germany – 22 January 1975 in Chile).
On 5 October 1940, Prince Karl married Princess Henriette Hermine Wanda Ida Luise Schönaich-Carolath (25 November 1918 – 16 March 1972). They divorced on 5 September 1946. They were the parents of three children:
- Prince Franz Wilhelm Viktor Christoph Stephan of Prussia (born 3 September 1943), he married Maria Vladimirovna, Grand Duchess of Russia, a claimant to the disputed Russian throne. Their child is Grand Duke George Mikhailovich of Russia, Prince of Prussia, born 13 March 1981 in Spain.
- Prince Friedrich Christian Ludwig of Prussia (3 September 1943 – 26 September 1943)
- Prince Franz Friedrich Christian of Prussia (born 17 October 1944).
After the divorce, Prince Karl married, morganatically, Luise Dora Hartmann (5 September 1909 Hamburg, Germany – 23 April 1961 Hamburg, Germany) on 9 November 1946. The childless couple divorced in 1959.
Prince Karl's last marriage was to Doña Eva Maria Herrera y Valdeavellano (10 June 1922 Lima, Peru – 6 March 1987 Lima, Peru) on 20 July 1959 in Lima, Peru. They were married until Prince Karl's death and had two daughters;
- Alexandra Maria Augusta Juana Consuelo Prinzessin von Preussen (born 29 April 1960 Lima, Peru)
- Désirée Anastasia Maria Benedicta Prinzessin von Preussen (born 13 July 1961 Lima, Peru).
- Leutnant (2nd Lieutenant), 1. Garderegiment zu Fuß (1st Regiment of Foot Guards)
- à la suite, 4. Gardegrenadierlandwehrregiment (4th Reserve Regiment of Grenadier Guards)
- Knight, Order of the Black Eagle
- Knight Grand Cross (with Crown), Order of the Red Eagle
- Knight, First Class, Prussian Crown Order
- Grand Commander, Royal House Order of Hohenzollern
- Knight, First Class, Order of the Netherlands Lion, Netherlands
- Knight, First Class (Star with diamonds), Osminieh Order, Ottoman Empire (Turkey)
Military Decorations (1914-1918)
- Iron Cross, Second Class
- Iron Cross, First Class