This article is based on the linguistic study of the formation of the Frankish and its influence on the field of onomastics. The article highlights the opinions of historical researchers about the gradual formation of the Frankish period since ancient times, and sometimes these opinions create polemics between them. At the same time, it is said that throughout history, various tribes gathered in the territory of the Frankish empire and created a state and language, and these tribes' languages influenced on the field of onomastics. The article also reflects the presence of mythical considerations in the field of onomastics, the inclusion of an important lexicon in the field of toponymy as a result of the German occupation, as well as in the vocabulary of Gallo-Romance.