It is one of the earliest studies in Russian historiography devoted to the peculiarities of the legal status of foreign confessions in Russia. It consists of two parts. The first part, based on archival materials from the Ministry of Foreign Affairs, contains a detailed analysis of various issues related to the construction of Protestant churches and the activities of Protestant clergy in the Muscovite state. This topic is considered from the standpoint of implementation of the principles of freedom of conscience and the boundaries of its application to the heterodox population of Russia. The second part of the book presents the history of the construction of the first Catholic church in Moscow, as well as some related legal aspects. The author comes to the conclusion that, from the second half of the seventeenth century, unlike Catholics, Protestants in Russia enjoyed not only the inviolability of their personal religion, but also got the right to unhindered public worship. There is also an Appendix with newly discovered archival materials.