The paper reviews the Marxist theory of the State around the concepts of relative autonomy of the state, hegemony, hegemonic crisis, ideology and ideological state apparatuses (ISAs). The theory is then applied to a case to demonstrate their continuous connection and ability to explain political and sociological phenomena. The chosen case is the military coup of 1980 in Turkey and the shift in ideology and hegemony along with this coup. It was observed that a hegemonic crisis preceded the coup and with the relative autonomy of the state, the military regime helped form a new hegemony which soon established its new ideology. The shift in the political ISA after the coup is analyzed as an example of the new ideology. It is argued that the political centre shifted to the right and the politics moved away from the class-based left-right axis.