The First Crusade was the greatest event of the Middle Ages, changing the history of Europe and the countries of the East. It is generally accepted that it began at the call of Pope Urban II, when thousands of knights set out to recapture the Holy Land from the Muslims. But what if the initiative did not actually come from Rome at all? Drawing on little-studied sources, British historian Peter Frankopan offers his perspective on these events. He considers the true inspirer and organizer of the First Crusade to be the Byzantine Emperor Alexios I Komnenos, a talented diplomat who miraculously remained on the throne, but at the same time managed to put the military resources of Europe at his service. Page by page, Frankopan unravels the intricacies of versions and sources, exposes the “black legend” of the “treacherous” emperor and, revealing the unknown history of the First Crusade, shows the consequences of this expedition for East and West.