Low German

The West Germanic languages, except for High German, of the Germanic branch of Indo-European, represented by Old Low Franconian, Old Saxon, Old Frisian, and Old English, and their later stages, including Dutch, Plattdeutsch, English, and Frisian. Old Low German is the Low German language from its earliest period to about the twelfth century. Middle Low German is the Low German language as written and spoken between circa 1100 and circa 1500.

"Low German" is generally contrasted with High German, which was historically spoken in Germany's more altitudinous southern terrain, including the Alps.

Note that the terms "Low" and "High", as used here, do not refer to social class, only altitude.