Low Saxon language (Plattdeutsch, Low German)
One of the two principal divisions of German, Plattdeutsch or Low German, includes Low Franconian, which is very closely related to Netherlandic (Dutch-Flemish) and is spoken only in the west, in a narrow fringe along the border between the Netherlands and Germany; and Low Saxon, which is used in the northern lowlands as far east and northeast as the Elbe River, including the cities of Münster, Kassal, Bremen, Hannover, Hamburg, and Magdeburg. As a result of the colonization of the Baltic regions by the Teutonic Knights, Low German spread throughout the lands east of the Elbe to Brandenburg, Mecklenburg, and Pomerania, as well as parts of Prussia.

Nowadays Low Saxon is maintained rather steadily in its native regions, though it gradually becomes closer to common official High German. The differences lie first of all in the prononciation. Phonetics have several serious differences between Low and High German tongues: High ei will be Low ie; ie > ee; z > t which reflects not only in orphography but in phonemes as well. The final -s in German turned into -t  in Saxon. Practically all these phonetic changes took place in ancient period, in the Old Saxon language, the parent tongue for English, Dutch, Frisian and Scots.