The present article reflects the results of research into the lexicon of unknown origin of the modern Germanic (English and German) languages. It is presupposed that the vocabulary specified was inherited from prehistoric idioms of ancient Europe and therefore belongs to heterogeneous Pre-Indo-European substrata. Original etymologies on the basis of revealed Germanic-Basque and Germanic-Caucasian parallels are suggested. The author postulates the participation of the Vasco-Caucasian component in ethnogeny of the Germans and differentiation of the Germanic languages.