The Germanic languages are one of up to ten branches of the Indo-European language family. (Others are Indo-Iranian, Armenian, Celtic, Italic, Albanian,
Balto-Slavic, and Tokharian.) All these languages, ancient and modern, have been traced to a common unrecorded original, Proto-Indo-European, which must
have been spoken around 3,000 BCE.
Image created by Multiple authors (Original work) [GFDL (www.gnu.org/copyleft/fdl.html)],
Click to open full size in a new window.
Scholars have traced the relationships between the languages and established their relative ages and which are closer to which. From internal and
archeological clues, they have tried to establish where the original Indo-European homeland was. The dominant theory is on the Central Asian steppes; a
popular rival theory, the "Kurgan theory," is around the Black Sea (with the mythic motif of the great flood originating from its rapidly filling after
a land bridge that had formerly made it a lake was broken through).
The first split between the languages--and hence the peoples--was into groups conventionally named after the word for "hundred" in Latin and Sanskrit:
centum and satem. The Germanic languages are in the centum group--along with the Italic, Celtic, and Hellenic languages and the extinct Tokharian, spoken
by the one group that went all the way east--to China. The Balto-Slavic languages are in the other group.
A map of the spread of Germanic peoples out of Scandinavia, skirting the issue of where they came from before that (or assuming they originated there):
Map created by Wiglaf, Wikimedia Commons
[1. Indo-European language image from http://en.wikipedia.org/wiki/File:IndoEuropeanTree.svg
2. Nordic Bronze Age image from http://upload.wikimedia.org/wikipedia/commons/d/d0/Nordic_Bronze_Age.png]