Prince Louis Ferdinand of Prussia (1907-94) was High Protector of the Order of Antioch from 1960 onwards. His father, Prince Wilhelm of Prussia, had been a member of the Order of the Crown of Thorns. His wife, Grand Duchess Kira Kirillovna of Russia, was the daughter of Grand Duke Cyril Vladimirovich of Russia, head of the Imperial House of Russia and also a member of the Order of the Crown of Thorns.
Prince Louis Ferdinand was the pretender to the throne of the German Empire from 1951 onwards. He is remembered for his opposition to the Nazi Party and his work as a businessman and patron of the arts.