Distribution of the primary Germanic groups ca. 1 CE.

North Sea Germanic has been proposed by the German linguist Friedrich Maurer who criticized the strict tree diagrams that had been used for the subdivision of language families since 19th century linguist August Schleicher. He rejected Anglo-Frisian as a historical subdivision of West Germanic.

Ingvaeonic is named after the Ingaevones, a West Germanic cultural group or proto-tribe along the North Sea coast. However, the identification of North Sea Germanic, the common ancestor of Old Frisian, Old English and Old Saxon with the language of the Ingvaeones is disputed.

Characteristics

Linguistic evidence for Ingvaeonic are common innovations observed in Old Frisian, Old English and Old Saxon such as the Ingvaeonic nasal spirant law, the loss of the Germanic reflexive pronoun, the monophthongization of Germanic *ai to ?/?, and deflexion such as the reduction of the three Germanic verbal plural forms into one form.

References

• Stefan Sonderegger (1979): Grundzüge deutscher Sprachgeschichte. Diachronie des Sprachsystems. Band I: Einführung ? Genealogie ? Konstanten. Berlin/New York: Walter de Gruyter. ISBN 3-11-003570-7

de:Nordseegermanische Sprachen nl:Ingveoonse talen