German dialects

German dialects are the various traditional local varieties of the German language. Though varied by region, those of the southern half of Germany beneath the Benrath line are dominated by the geographical spread of the High German consonant shift, and the dialect continuum that connects High German to the neighboring varieties of Low Franconian (Dutch) and Low German.

The varieties of German are conventionally grouped into Upper German, Central German and Low German; Upper and Central German form the High German subgroup. Standard German is a standardized form of High German, developed in the early modern period based on a combination of Central German and Upper German varieties.

Traditionally, all of the major dialect groupings of German dialects are typically named after so-called "stem duchies" or "tribal duchies" (German: Stammesherzogtümer) by early German linguists, among whom the Brothers Grimm were especially influential. These tribal duchies came into existence at the end of the Early Middle Ages within the Holy Roman Empire and were thought to have been continuations of earlier tribal lands which were subjugated by the Franks and incorporated into their realm at the close of the Migration Period.

For example, the Germanic tribe of the Bavarii (subjugated by the Franks during the 6th century) gave their name to the later stem duchy of Bavaria (817–1180), which itself would lend its name to the traditional Bavarian dialect grouping described in the early 19th century.

As their understanding of the Second Germanic consonant shift progressed, linguists (when applicable) further divided these dialects into groupings based on their degree of participation of this consonant shift, with "Low" (German: nieder-) signifying little to no participation, "Middle" (or "Central"; German: mittel-) meaning medium to high participation and "Upper" (German: ober-) conveying high to full participation.

Because the 19th-century classification nomenclature was based primarily on historical territories rather than linguistic clusters, the traditional system can imply greater similarities between dialects than is linguistically warranted. The best-known example of this phenomenon is found within the Franconian cluster, which is divided into Low Franconian, Middle Franconian and Upper Franconian even though the Low Franconian (incl. Dutch) dialects are not most closely related to Middle and Upper Franconian dialects within the larger continuum. In fact, of all German dialects, the Low Rhenish dialect (the only Low Franconian dialect spoken in Germany itself) is the most divergent when compared to Standard German, whereas the Middle and Upper Franconian dialects are fairly similar in their overall structure and phonology to the German standard language.

As a result, the second half of the 20th century saw a shift in academic customs, with many linguists instead describing dialect clusters based on the geographical area in which they are spoken (i.e. Meuse-Rhenish or Westphalian) and their degree of participation with the Second Germanic consonant shift, or, such as in the case of the influential linguists Friedrich Maurer and Theodor Frings [de], creating a new framework of dialect classification altogether.

Nevertheless, in common parlance it is common for speakers of German dialects to use the traditional/older nomenclature when referring to their particular dialect, stating, for example, that they speak Saxon, Bavarian, Allemanic (Swabian), Thuringian or Franconian.