King Christian VII was truly a mad king. He had shown symptoms of mental illness since childhood, and is speculated to have suffered from schizophrenia, and had tremendous mood swings. 

He was only King by title, but he was far from fit to rule. His court physician, Johann Struensee, had gained major political influence, but was executed after his affair with the Queen. King Christian was formal in the morning, but at night he would venture into Copenhagen for all sorts of debauchery.