Style of The French Sovereign - Francorum Rex

The Latin term Francorum Rex was the official Latin title of the "King of the Franks" after the accession of the Carolingian Dynasty (sometimes taking the form of Rex Francorum); this title was used in official documents until French replaced Latin as the formal language of legal documents, and remained used on coins until the 18th century. However, from as early as the 12th century, the form Franciae Rex ("King of France") was also used.