The Carolingians followed the Frankish custom of dividing inheritances among the surviving sons, though the concept of the indivisibility of the Empire was also accepted. The Carolingians had the practice of making their sons (sub-)kings in the various regions (regna) of the Empire, which they would inherit on the death of their father. Though the Carolingian Empire may have several kings, the imperial dignity was accorded only to the oldest son.
