The Byzantines called it Tamatarha, the Genoese—Matrega, and the Russians—Tmutarakan. A mysterious semi-mythic principality, a fortress of Kievan Rus in the Black Sea region, standing at the crossroads of the chivalric West and the Arab East. It bordered not only on enlightened Byzantium, but also on warlike Alania, and on the steppe lands of the Cumans. Twice, Tmutarakan flashed in Russian chronicles, but it perished after the poisoning of Rostyslav Vladimirovich—the first exile-prince in Rus… But what if the hand of the poisoner had been stopped? What if the dynasty of Russian princes had been established in the North Caucasus and united the surrounding tribes? A shield against the coming Mongol invasion—or a new center for the unification of Rus?