In 1939 the Austrian historian subordinated the feudal state as secondary to his concept of a "Personenverbandsstaat" (personal interdependency state), understanding it in contrast to the territorial state. This form of statehood, identified with the Holy Roman Empire, is described as the most complete form of medieval rule, completing conventional feudal structure of lordship and vassalage with the personal association between the nobility.  But the applicability of this concept to cases outside of the Holy Roman Empire has been questioned, as by Susan Reynolds. The concept has also been questioned and superseded in German histography because of its bias and reductionism towards legitimating the Führerprinzip.