Duke of the Franks

The title Duke (and Prince) of the Franks (Latin: dux (et princeps) Francorum) has been used for three different offices, always with "duke" implying military command and "prince" implying something approaching sovereign or regalian rights. The term "Franks" may refer to an ethnic group or to the inhabitants of a territory called Francia.

The first office was that of the mayors of the palace of the Merovingian kings of the Franks, whose powers increased as those of the kings declined. The second was that of the second-in-command to the early kings of France, the last incumbent of which succeeded to the throne in 987. This title was sometimes rendered as Duke of France (dux Franciae). The third instance was that of the rulers in East Francia (now Germany) of the so-called "tribal" duchy of Franconia.