Ключевые слова: клятва, рота, шерть, подданство, гражданство Древняя Русь, Московское царство, Российская империя, Российская Федерация

Inclusion of the clause on the oath at naturalization in the Federal Law “On Citizenship of the Russian Federation” in 2017 makes understanding of historical experience of such an institution in Russia in the past, relevant. The paper is an attempt of comparative legal study of the modern institution of the oath at naturalization and similar institutions that existed in the Ancient Rus’, Moscow state, Russian Empire. It is emphasized that for a long time the institution of the oath was not formaly established; however, it was established at first in relation to natives of Eastern countries, while the oath of Europeans who accepted a Russian citizenship was not regulated in form and content. Authors raise the question to what extent the historical traditions of our country were taken into account in the development of the modern oath of Russian citizenship. To answer this question, the basic elements of the institution of the oath including terms of adjuration, ceremonial, content and legal formalization have been examined. The study is mainly based on the formal-legal, historical-legal and comparative-legal methods.