He had a very unhappy childhood. His father was King and he was a very eccentric fellow and he was obsessed with the military. Frederick’s father wanted a son who would be a great general and make their kingdom a great military power. Frederick was not a very impressive young man, he was slight and weak. He was also a bookworm and loved to play the flute. The son was very different from the father and this led to problems. His father scolded him constantly in public, he often had him punished. There was even an attempt to remove Frederick from the succession and to make his younger brother the heir to the throne of France.
Frederick was so unhappy that he ran away and he was later forced to return home. A young man, his best friend, had helped him to escape and Frederick’s father ordered the execution of the young man and he forced Frederick to watch his best friend beheaded and then imprisoned him for a while as a punishment. This was to make Frederick for life and caused him to have nightmares throughout his life