The Franks appear in Roman sources in the third century as a grouping of peoples on the lower Rhine, serving in the empire and raiding it by turns. Ian Wood's study of the Merovingian kingdoms describes the century after Clovis as the construction of a genuine state out of that material: a partible inheritance that split the realm among sons at every succession, an aristocracy holding land and office together, and bishops who were very often members of it.
Religion supplied both administration and frontier. Irish and Anglo-Saxon missionaries, Columbanus and later Boniface among them, founded monasteries across Frankish territory and pushed the church eastward into Frisia and Thuringia with Frankish military backing behind them. Boniface was killed in Frisia in 754 and became a martyr of that expansion.
The dynasty changed in 751, when Pippin, the mayor of the palace, took the crown with papal endorsement, and his son Charlemagne turned the arrangement into an empire, crowned at Rome in 800. The Saxon wars that filled much of his reign made conversion a condition of surrender, with capitularies imposing death for refusing baptism, and the alliance of Frankish arms with the papacy set the shape of western European Christendom for centuries afterwards. The name of the people became the name of a country it no longer governed.