"Younger brother Alexander hated dashing, erratic Crown Prince George (1887 - 1972), darling of the Serbian people, so he framed him as a loony, got him exiled, and in due course became King instead. George made the mistake of writing an insulting letter and going back home on the heels of it. Now, in a remote Yugoslavian villa, surrounded by trees, hedges, and mustachioed detectives, the Serbian Bad Boy lives in solitary confinement, doing mathematical problems to keep from getting bored."
A 1938 article which gave a brief account of the incarcerated Crown Prince George of Serbia. As the above makes clear, he was judged insane and locked up between the years 1925 through 1939. He was set free by the Nazis during their brief occupation of that country.
Click here to read about the 1922 discovery of King Tut's tomb.