The paper focuses on the historical discourse produced by the “Caliphate of the Islamic State,” a quasi-state that existed from 2014 to 2017 and was created by a terrorist group (it was not recognized by any country in the world; in 2014 the Supreme Court of the Russian Federation banned its activities in Russia). Particular attention is paid to the ways, in which ideologists of the "caliphate" utilized their appeals to the early Islamic historical past in the processes of state-building, constructing “the hostile Other”, and shaping territorial identity of the quasi-state. Such appeals were employed to construct an ideal order to be strictly followed, to legitimize the dominant role the Islamic State’s ideologists as interpreters of this order and to mobilize one’s own group against “the hostile Other”. In the process of constructing the “ideal caliphate” of the past, ideologists took out of historical contexts both various features of those governmental systems that existed in different periods and markedly confrontational archaic practices of medieval Muslim states’ relations with the outside world.