From Damn Interesting’s “Feral Children“:
One of the more mysterious cases is that of Kaspar Hauser, who was discovered in Nuremberg, Germany in 1828. He was unsteady on his feet, held a letter for a man he had never met, and only spoke the phrase “I want to be a horseman like my father is.” The letter was addressed to the captain of the 4th squadron of the 6th cavalry regiment:
I send you a lad who wishes to serve his king in the Army. He was brought to me on October 7th, 1812. I am but a poor laborer with children of my own to rear. His mother asked me to bring up the boy, and so I thought I would rear him as my own son. Since then, I have never let him go one step outside the house, so no one knows where he was reared. He, himself, does not know the name of the place or where it is.
You may question him, Honoured Captain, but he will not be able to tell you where I live. I brought him out at night. He cannot find his way back. He has not a penny, for I have nothing myself. If you do not keep him, you must strike him dead or hang him.
Kaspar was about sixteen years old, but he behaved like a small child. At first, when a mirror was handed to him he would look behind it trying to find the person behind the mirror, and he burned his hand while touching a candle’s flame in curiosity. Kaspar had excellent night vision and a keen sense of smell. He detested meat and alcohol, and was offended by the smell of flowers. Unlike many of the other cases described here, Kaspar did learn much over time, eventually learning to speak enough to describe the small cage in which he had been raised, and the mysterious keeper who finally released him outside of town. But about five years after appearing from nowhere, Kaspar was assassinated. The reason for his murder might be because some believed he was the missing heir to the throne of Baden. His assassin lured him away under the pretense that they would reveal who his parents were, and stabbed him fatally in the chest. The mystery of his early life and violent death has never been satisfactorily answered.