The article analyzes the subject of interethnic relations in the interpretation of the Russian national of Polish origin Marian Edmundovich Zdziechowski – linguist, theorist of Russian literature, religious thinker, philosopher, publicist and public figure. Researchers from many Slavic countries turn to the study of Zdziechowski's ideological heritage, since his sphere of scientific interests, as he himself claimed, consisted of "the study of Slavs." While we acknowledge the extensive work done in this field, we must admit that Zdziechowski's works published in Russian periodicals of the pre-revolutionary period are still insufficiently involved in the field of research. It is this gap that this article seeks to fill. The article presents and analyzes Zdziechowski's opinions on the current system of interethnic relations in imperial Russia and the cultural policy pursued at that time regarding national minorities. It is shown that in presenting his views, Zdziechowski relied on the authoritative opinions on this issue of well-known Russian cultural figures of the time: Leo Tolstoy, B.N. Chicherin, G.N. Trubetskoy, A.N. Pypin, and V.D. Spasovich. Although the problems of interethnic relations were considered by Zdziechowski mainly at the example of the analysis of Russian state policy towards Poles living in the country, his opinions are regarded as important for understanding the nature of the imperial ethnic policy in general. The editors of Moskovsky Ezhenedelnik and Novoye Zveno, where his texts were published, give their appraisals of Zdziechowski's activities. The evolution of the thinker's views from the expressions of hope for a beneficial solution of the Polish question to the emergence of a sense of disappointment and pessimism is traced. The coverage of this problem in the historical perspective shows the ambiguity of its interpretations and solutions in the past, which might help to improve the national policy in modern Russia.