In 1876, Wenker earned his Ph.D. degree in Tübingen with a dissertation topic on the shifting of German root syllables.

Wenker's first effort to map spoken dialect began in 1876 and involved surveying schoolmasters in northern Germany.

Each questionnaire contained forty sentences, ranging from simple to somewhat difficult, and offered multiple points from which the local dialect could emerge.

Wenker continued collecting questionnaires after the publication of his atlas, but it took more than forty years for his vision to be realized.

Inevitably perhaps, later dialectologists found Wenker's data, which was rich in phonological and word-structure information, to be too limited in terms of lexical and syntactic variants.