Frederick William II, Prince of Prussia, had a terrible relationship with his father growing up. Frederick preferred music to martial pursuits and his father thought him effeminate, weak, and unworthy to be heir to a militant kingdom like Prussia. In fact, Frederick Wiliam I often beat his son in public, trying to toughen him up. By 18 Frederick had had enough. He decided to run away with his best friend, and presumed lover, Han Hermann von Katte.
They didn’t get very far before they were discovered, caught, and imprisoned. Frederick was almost executed, but his father’s will unsurprisingly softened. His friend was not so lucky. Von Katte was beheaded and Frederick was forced to watch. They were so close that Frederick was able to beg von Katte’s forgivness, and receive it, before he died. Frederick spent the next ten years under his father’s thumb.