John William, Duke of Jülich-Cleves-Berg

Who was John William, Duke of Jülich-Cleves-Berg?

Johann Wilhelm of Jülich-Cleves-Berg was a Duke of Jülich-Cleves-Berg.

His parents were William the Rich, Duke of Jülich-Cleves-Berg and Maria of Austria, a daughter of Ferdinand I, Holy Roman Emperor and Anna of Bohemia and Hungary. He grew up and was educated in Xanten. Johann Wilhelm became Bishop of Münster. However, after the unexpected death of his elder brother Karl Friedrich, Wilhelm was needed to succeed his father as Duke of Jülich-Cleves-Berg, a secular fief. He was also Count of Altena. The United Duchies of Jülich-Cleves-Berg was a combination of reichsfrei states within the Holy Roman Empire.

Johann Wilhelm was first married in 1585 to Jakobea of Baden, daughter of Philibert, Margrave of Baden. He was secondly married to Antonia of Lorraine, daughter of Charles III, Duke of Lorraine.

He was subject to mental illness, for which he was treated by the physician Francesco Maria Guazzo.

Upon Duke Johann William's childless death in 1609, his inheritance was claimed by the heirs of his two eldest sisters: the heir of Maria Eleonora of Cleves, the eldest sister and married to Albert Frederick, Duke of Prussia, was Anna of Prussia, the Electress of Brandenburg, a Protestant.