The book is dedicated to the history of the Byzantine Empire from the era of the Crusades to the conquest of Constantinople by the Ottomans. Professor A.A. Vasiliev (1867–1953), an outstanding Russian scientist, whose works on the history of Byzantium are known throughout the world from Russia to the USA. There are very few general histories of Byzantium written by one researcher, and one of them is the work of A.A. Vasiliev, offered to the reader. The book is written briefly, clearly and accessible, contains an extensive scientific apparatus that allows you to make inquiries and understand the problems of the late period of Byzantine history. These indisputable and very important advantages of A. A. Vasiliev’s work will ensure its long life among a fairly wide range of readers.