Middle Low German is a developmental stage of Low German. It developed from the Old Saxon language in the Middle Ages and has been documented in writing since about 1225/34 (Sachsenspiegel). During the Hanseatic period, Middle Low German was the leading written language in the north of Central Europe and served as a lingua franca in the northern half of Europe. It was used parallel to medieval Latin also for purposes of diplomacy and for deeds.
Northern Europe in 1400, showing the extent of the Hanseatic League
Der Keyserliken Stadt Lübeck Christlike Ordeninge/ tho denste dem hilgen Evangelio/ Christliker leve/ tucht/ frede unde enicheyt/ vor de yöget yn eyner guden Schole[n] tho lerende. Unde de Kercken denere und rechten armen Christlick tho vorsorgende. Dorch Jo. Bugen. Pom. beschreven. 1531, i.e. "The Imperial City of Lübeck's Christian Ordinance at the service of the Holy Gospel of Christian life, discipline, peace and unity, to teach the youth in a good school, and to provide Christianly for the church servants and the righteous poor. Written by
Eyne vorrede ouer dyt boek van reynken deme vosse, i.e. "A prologue about this book of Reynard the Fox". Reynard the Fox is an allegorical epic that was popular in medieval Europe. This is from the 1498 edition published in Lübeck, one of the major Hanseatic cities. The typeface is typical for the blackletter used in MLG printing.
Early New High German (ENHG) is a term for the period in the history of the German language generally defined, following Wilhelm Scherer, as the period 1350 to 1650.
The diphthongization of long vowels in ENHG