Prince Nicholas of Greece and Denmark was the son of which king that was assassinated in 1913?
George I of Greece George I (Greek: Γεώργιος Α΄ , "Geórgios I"; born Prince William of Schleswig-Holstein-Sonderburg-Glücksburg; 24 December 1845 – 18 March 1913) was King of Greece from 1863 until his assassination in 1913.
Prince Igor Constantinovich of Russia Prince Igor Constantinovich of Russia ("Игорь Константинович") (10 June 1894 – 18 July 1918), was the sixth child of Grand Duke Constantine Constantinovich of Russia by his wife Elisaveta Mavrikievna née Princess Elisabeth of Saxe-Altenburg.