The presented article is devoted to a comprehensive analysis of the legislative powers of the Grand Prince of Kyivan Rus. The author examines the origin and evolution of the title “Grand Prince,” clarifying its chronological boundaries and political significance. Various scholarly approaches are compared – from dating the emergence of the title to the 9th century to limiting its spread to the second half of the 12th century. It is emphasized that even in the absence of an established official status, the title served to elevate the authority of the Kyivan ruler as the senior among the princes. The positions of prominent historians and legal scholars — M. Hrushevsky, V. Kulchytsky, I. Boiko, I. Grekov, and others – are summarized, all of whom acknowledge that Kyivan legislation was formed as a combination of princely decrees and the customary law of the community, while the Grand Princes themselves played a key role in reforming and unifying the legal system, repealing or amending local norms. The author provides a detailed analysis of the lawmaking activities of individual princes. It is established that Oleg’s treaties with Byzantium in 907 and 911, known as “Oleg’s Rus’ Law,” contained provisions regulating trade, criminal law, inheritance relations, and the return of fugitives, and became an important stage in the written codification of law. Princess Olga reformed the system of tribute collection by introducing clear “ustavs” (statutes) and “uroks” (tax norms) and establishing administrative units – “pogosts” and “stanovishcha” – which ensured regular revenues and reduced abuses. Under Volodymyr the Great, the Christianization of Rus’ initiated interaction between secular and ecclesiastical jurisdictions and led to the sanctioning of criminal law norms, in particular regarding the punishment of robbers after proper investigation, thus promoting the principles of justice. Under Yaroslav the Wise, the “Pravda of Yaroslav” was created – the first written code of laws that limited blood vengeance, protected the individual and property, regulated inheritance relations, and established a unified legal order throughout the entire territory of the state. His sons continued the codification work, feudalizing the law and strengthening the protection of the interests of the ruling class. The final stage was marked by the activity of Volodymyr Monomakh, whose “Ustav” limited usury, curbed creditor abuses, protected hired workers, and regulated credit and inheritance relations, reflecting a socially oriented character.
B. I. Hutiv (Thu,) studied this question.