Inscriptions, a type of source which has hitherto hardly been taken into account in historical linguistics, can provide data for a whole series of questions thrown up by research into the linguistic geography of Early New High German and the Late Middle Low German of the same period. In respect of the pressure towards standardization exerted by M. Luther's bible, various degrees can be differentiated. The greatest willingness to adopt this linguistic norm is found in the case of New High German monophthongization and diphthongization, as well as in the lowering of u to o before nasals and the use of the verbal prefix ver-. In these cases, the symbols on the appropriate maps show agreement with Luther 's usage. In some other cases, namely, the use of for MHG /ei/, the occurrence of vowel forms without unrounding, the use of the uncontracted form of the word nicht and the use of the subjunctive in the predicates of concessive clauses, we find that the form favoured by Luther is the one which appears most frequently in the inscriptions. Nevetheless, especially in sixteenth-century inscriptions, we find several examples of the replacement of standard forms by deviant variants valid at the same time. In contrast, the number of deviations from Luther's language visibly decreases in the seventeenth century. In some cases, the treatment of the norms of the Luther's bible in the inscriptions indicates that the linguistic usage of the reformer had no or only indirect significance for the course of development here. Thus, in the case of the feminine inflectional system, while it is true that the epigraphic sources largely follows Luther's practice, but it is also the case that from about 1600 on a tendency towards deviation from his usage emerges. Here, restructuring is a process which was clearly not influenced by Luther. Again, in the case of abstract suffix -nis, the course of development seems to have been determined by factors inherent in the language rath