First consonant mutation

The first consonant mutation is a phonetic modification that affected the Proto-Indo-European occlusive consonants in the Germanic languages ​​(so it is often known by its German name: erste Germanische Lautverschiebung) and in Armenian. Currently the process is located around the fifth century.

Its modifications are described by the laws of Grimm and Verner (in fact, it is often assimilated to the first of these, the second being a simple refinement that explains some exceptions).

Among the Germanic languages, certain southern dialects of the western branch still underwent a new phonetic modification called the second consonant mutation, all of which gave rise to high German (standard German base).

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