Proto-Germanic language

Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages. Proto-Germanic eventually developed from pre-Proto-Germanic into three Germanic branches during the fifth century BC to fifth century AD: West Germanic, East Germanic and North Germanic, which however remained in contact over a considerable time, especially the Ingvaeonic languages (including English), which arose from West Germanic dialects and remained in continued contact with North Germanic. A defining feature of Proto-Germanic is the completion of the process described by Grimm's law, a set of sound changes that occurred between its status as a dialect of Proto-Indo-European and its gradual divergence into a separate language. The end of the Common Germanic period is reached with the beginning of the Migration Period in the fourth century. The alternative term "Germanic parent language" may be used to include a larger scope of linguistic developments, spanning the Nordic Bronze Age and Pre-Roman Iron Age in Northern Europe (second to first millennia BC) to include "Pre-Germanic" (PreGmc), "Early Proto Germanic" (EPGmc) and "Late Proto-Germanic" (LPGmc). While Proto-Germanic refers only to the reconstruction of the most recent common ancestor of Germanic languages, the Germanic parent language refers to the entire journey that the dialect of Proto-Indo-European that would become Proto-Germanic underwent through the millennia. The Proto-Germanic language is not directly attested by any coherent surviving texts; it has been reconstructed using the comparative method. However, there is fragmentary direct attestation of (late) Proto-Germanic in early runic inscriptions (specifically the second-century AD Vimose inscriptions and the second-century BC Negau helmet inscription), and in Roman Empire-era transcriptions of individual words (notably in Tacitus' Germania, AD 90). Some sources also give a date of 750 BC for the earliest expansion out of southern Scandinavia and northern Germany along the North Sea coast towards the mouth of the Rhine.