The family of Iranian languages consists of several groups, of which the Kurdish language(s) is among the most diverse and problematic. Lack of authentic knowledge of the present state of Kurdish languages and, in some cases, the absence of proper methodologies are among the main obstacles in the way to proper historical study of these languages. Among the most complicated issues in Kurdish studies is Gurani. Common to most linguistic studies of Gurani is their assumption of a mass migration of the Kurds from the Caucasus and northern Iran to the central Zagros area and a subsequent assimilation of local groups including the ‘Gurāns’. We have investigated the data and the assumptions of some of the more influential researches and have attempted to shed a new light on the concept of ‘Gurani’. The outcome of this study—besides a critique of the methodology of linguistic approaches to Gurani—is the redefinition of Gurani not as a distinct practical language or dialect but as a literary idiom which, cannot be cast into any linguistic categories. It is also shown how Gurani has played a vital role in preserving and transmitting cultural data of diverse groups of people in the Zagros area.