The Christianity that arrived in the Netherlands with the Romans appears not to have died out completely (in Maastricht, at least) after the withdrawal of the Romans in about 411. The Franks became Christians after their king Clovis I converted to Catholicism, an event which is traditionally set in 496. Christianity was introduced in the north after the conquest of Friesland by the Franks. The Saxons in the east were converted before the conquest of Saxony, and became Frankish allies.

Hiberno-Scottish and Anglo-Saxon missionaries, particularly Willibrord, Wulfram and Boniface, played an important role in converting the Frankish and Frisian peoples to Christianity by the 8th century. Boniface was martyred by the Frisians in Dokkum (754).