About the book: 2013 / The book analyzes from a critical point of view the generally accepted concept of Prince Igor’s campaign in the Polovtsian steppe to the south of the Black Sea Don. A hypothesis has been expressed about a completely different direction of the campaign, namely to the west, to the north of the Adriatic, to the valley of the Po River (Eridanus). This is due to the peculiarities of the process of conquest by the Slavic peoples in the 5th–6th centuries of the Balkans, Greece and the Northern Mediterranean. In “The Tale of Igor’s Campaign” (SPI), the ancient poet showed, in the author’s opinion, the final stage of Slavic expansion in the central part of the former Roman Empire, and revealed the reasons why the ancient Russians were unable to retain this overseas territory (the land of Troyan) as their vassal. The book makes an attempt, in the light of the new theory, to comprehensively reveal the dark places of the SPI, and also presents a poetic translation in an alternative form to the readers. The material in the book is presented in a simple and accessible form. The book is intended for a wide range of readers who are interested in Russian history..