Upper German

Definition and stakes

Friedrich Kluge,  An Etymological Dictionary of the German Language (1891)

“ Compare Middle High German ze diute, ‘distinct, evident,’ and ‘in German’ (diute, dative singular of diuti, tiute, feminine, ‘exposition, explanation’) ; note too Anglo-Saxon geþeóde, ‘language’ (as the main characteristic of the nation) .
deutsch, adjective, ‘German,’ from the equivalent Middle High German diutsch, tiutsch; the initial d of the Modern High German and Middle High German words is Middle German, the earlier form, teutsch (Middle High German tiutsch) , is Upper German, and was, especially by the UpGer. writers, constantly used till the end of the last century.
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Source: Wikisource

Portrait of Johann Wolfgang von Goethe Johann Wolfgang von Goethe,  The Autobiography of Goethe

“ The Upper-German, and perhaps chiefly he who lives by the Rhine and Maine (for great rivers, like the sea-coast, always have something animating about them) , expresses himself much in similes and allusions, and makes use of proverbial sayings with a native [Pg 211] common-sense aptness. In both cases he is often blunt, but when one sees the drift of the expression, it is always appropriate; only something, to be sure, may often slip in, which proves offensive to a more delicate ear. ”
Source: Gutenberg

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