The present diploma thesis deals with the development of the general part in the private law and subdivides into two general parts. The first section, for the sake of clarity, presents the „objective“ of the development, i.e. the general part of the German Civil Code itself. Subsequently, the processed field of view is limited and two eras of special importance for the formation of the general part are presented: The Rational Law era on the one hand and the era of the German Historical School on the other. The first main section concludes with the presentation of the genealogy of the general part in legal textbooks. For this purpose, the works of the main authors of the respective periods are illustrated in chronological order and by their systematic structure. The second main section deals with the incorporation of the general part into law, starting off with the description of the general codification. Subsequently, the first natural law codification wave and the ensuing second, pandectistic codification wave, along with the respective codes of law, are described. This section also contains the illustration and comparison of the different structures of the aforementioned codifications and shows how and when the general part was introduced into the German Civil Code. Finally, some of the General Parts advocates and critics arguments are reproduced and the thesis is concluded by a summary and closing remarks.