Germanic kingship refers to the customs and practices surrounding kings among the pagan Germanic tribes of the Migration period (circa AD 300-700) and the kingdoms of the Early Middle Ages (circa AD 700-1000). The title of king (Proto-Germanic:*kuningaz) is in origin that of the leader elected as sacral and military leader from out of a noble family, usually considered of divine ancestry, in the pagan period.
The Germanic monarchies were originally pagan, but their contact, during the Völkerwanderung or Migration Period, with the Roman Empire and the Christian Church greatly altered their structure and developed into the feudal monarchy of the High Middle Ages.
The term "barbarian monarchy" is sometimes used in the context of those Germanic rulers that after AD 476 and during the 6th century ruled territories formerly part of the Western Roman Empire, especially the Barbarian kings of Italy. In the same context, Germanic law is also termed leges barbarorum "barbarian law" etc.
Read more about Germanic Kingship: Terminology, Germanic Pagan Kingship, History, List of Germanic Monarchies