The Middle High German reference article from the English Wikipedia on 24-Jul-2004
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Middle High German

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Middle High German is an ancestor of the modern German language, and was spoken from 1050 to about 1500. Some linguists prefer to use 1350 as the end of the Middle High German period, calling the period from 1350 to 1750 Early New High German.

Dialectically, the Middle High German language is divided into:

  1. Upper German (Oberdeutsch), comprising Alemannic and Austro-Bavarian; and,
  2. Central German (Mitteldeutsch), comprising the Franconian dialects and East Central German (Ostmitteldeutsch).