IntroductionWhen thinking of ideology, one tends to conceive of it as a configuration of strategic and convergent set of ideas. However, the argument of this paper is founded on the premise that, while a given ideology is supposed to be fed from a clearly identifiable and convergent set of causes and principles, in reality it is often rooted in seemingly divergent and even antagonistic ideas, which can take up different guises within the same context. In other words, from such a perspective, ideology is defined as a body of ideas that, against the commonsense understanding, strategically harbors seemingly opposing ideas that can supplement each other in particular ways. Iran, particularly after 1979 revolution, is a prime example of a country where the state's ideology has been nourished by explicitly divergent ideologies. Specifically, Iran is a country where the state's theocratic-political ideology sometimes goes hand in hand with the nation's plea for a return to the old Persian identityan unwelcome identity from the point of view the post-revolutionary state-to provide a basis for unity in the fight against an external other.An interesting recent situation in which the commonly-supposed anti-state idea of return to Old Persian identity showed its consolidating role in relation to the state ideology can be observed in the reaction of the Iranian Islamic state and its society to the threat of the Islamic State (ISIS). While for the Iranian Shia government, ISIS is considered a serious 2 enemy embodying radical Sunnism, for those Iranians who emphasize their Persian identity, ISIS precisely represents a menace to this pre-Islamic national identity. Now the question that can be raised here is through what mechanism two seemingly opposing sources feed a unified ideology? To put it another way, what is the specific feature of each ideological cause that enables each to supplement the other one?To answer the above question, one needs, before analyzing the ideological apparatus itself, to explain the complexity that the convergence of the two ideological causes give rise to. This complexity can be explained by referring to the fact that the Iranian Islamic State has not adopted a clear standpoint with regards to the notion of Persian heritage and identity. This equivocal positioning of the state is perhaps affected by the fact that it realizes that there are still a noticeable number of Iranians, particularly among the middle-class, who believe that Persian heritage is an essential source which can give a unique dimension to their identity, an aspect reminiscent of an ancient and powerful civilization with sophisticated system of governing and value system as well. Hence the Iranian state is not willing to unequivocally refute the Persian identity. At the same time, the state has no alternative but to put emphasis on its Islamic principles, rather than on Persian heritage, as this is what, according to postrevolutionary leaders, distinguishes their value system from that of the pre-revolution state and also from th...