(1911-1987) Adolf Hitler’s nephew; raised in Liverpool by Hitler’s half-brother Alois Hitler, then relocated to the U.S. where he served in the Navy during World War II against his half-uncle. Changed his surname post-war to Stuart-Houston. Very rare war-date signature, rank and free frank accomplished on a transmittal cover also addressed in his hand to a ‘Miss Conboy’, Sampson, NY, March 29, 1944. In full: ‘William P. Hitler A.S. Co. 104 C.2. U.S.N.T.S. Sampson, N.Y.’ Light toning, top and right side neatly split for opening, near fine.