Introduction: the article analyzes the legal significance of the legend about the founding of Rome as illustrated by the episode concerning the murder of Remus, brother of Romulus. This myth, as a legal narrative, preserved the description of facts that corresponded to the logic of Roman criminal law and were constantly updated in the public consciousness. Purpose: the article attempts, from the stance of postclassical jurisprudence, to reconstruct the legal reality of ancient Roman society and the Romans’ understanding of the death of Remus, to analyze the reasons for the stability and the development stages of the narrative tradition. Results: the episode of fratricide, reflected in most ancient sources, is contextually connected with public legal consciousness, which, throughout most of the Roman history, did not condemn Romulus. The symbolic interpretation of the legend is insufficient since it does not take into account the normative enshrinement and positivation of the mythological plot in the Digests. The narrative does not contain a detailed description of the ritual, and therefore Rem’s death cannot be considered a sacrifice. The analyzed legend reflects the process of establishing ancient Roman legal norms, and its content is more of legal than of religious or allegorical nature. Conclusions: the narrative about the death of Remus can be recognized as a source of archaic law. Its regulatory content was expressed in the prohibition to get over the walls or ditch surrounding the city, which served to preserve Roman society and supported the idea of law and order and the inevitability of punishment. The ban itself as well as the sanction for violating it were publicly proclaimed. The preservation of the narrative tradition is explained by the focus on repeated application of the described rule, the violation of which was punished regardless of blood relationship. The myth of Romulus and Remus initially legitimized the archaic criminal law norm, giving it the properties of publicity, universality, and obligation. Evolving in dialogue with the audience, this legend acquired the properties of a metanarrative that personified the inviolability of Roman laws and created the principles of the entire system of Roman public law.