Iranian epic literature can be divided into two branches: western and eastern Iran. It can also be divided into three historical periods: ancient, middle, and modern. This chapter will examine and describe the Iranian epic literature in western Iran through the lens of the Gurāni language. It will explore epic literature of the ancient period during the Elamite, Median, and Achaemenid eras, influenced by Mesopotamian civilizations, Scythian culture, and Avestan literature. In the middle period, the Parthian and Sassanid epic literature will be examined, meanwhile considering the distinctiveness of Achaemenid and Avestan narratives and the influence of Greek culture. The Iranian epic literature of this period will be recognized in two eras: (1) from Kayumars to Bahman, and (2) from Kayumars to Yazdegerd, as reflected in Pahlavi texts and the Khodāynāmeh. In the modern period (post-Islam), Shāhnāmeh writings and epic storytelling in the early Islamic centuries and Shāhnāmeh storytelling in the Gurāni language are analyzed. Gurāni Shāhnāmeh represents a comprehensive period in the history of mythical-epic Iran in a rhyming poetic structure of mythical prose and oral sources. This research will also examine the reflection of Gurāni Shāhnāmeh in the illustrations of handwritten copies of Ferdowsi’s Shāhnāmeh and the ritual texts of the Ahl-e Haqq community.