The Turban helmet is a type of war helmet during the 14th to 16th centuries AD in Middle East countries. This type of helmet has become known by Western scholars by this name because of the special decorations that made it look like a turban as well as the visibility of the helmet from under the warriors’ turban. Based on the numerous documents remaining, one can say that the use of Turban helmets was popular in Middle East territories’ armies during the Middle Ages. Despite being widely used and in style for more than two centuries and among many west Asian countries, among all the remaining samples of this type of middle eastern helmet, only two distinct styles, the Turkoman and the Ottoman styles, have been examined and introduced. This can be due to a large number of remaining samples of these two being kept for years in the armouries of the Ottoman Empire. Apart from these two known styles, few studies have been done so far on investigating other possible types of turban helmets. The purpose of this research is to study the turban helmets that were popular among the armies of the Il-khanid, Jalayirid, Muzaffarid, Timurid, Turkoman, and Safavid that ruled respectively in the cultural Iran region, by relying on the remaining documents from the 14th to the 16th centuries, such as the collection of helmets and illustrated manuscripts. The results of this research reveal that the changes that occurred in the making of turban helmets during the 14th to the 16th centuries have led to the representation of four different types of helmets: Mongolian style, Timurid style, Turkoman style, and Qizilbash style.

The historical fortress of Aq-Qalih, a large and little-known structure in the Juvayn Plain of northern Khorasan, is tentatively attributed to the Mongol Ilkhanid period based on limited prior studies. However, extant Ilkhanid -period documents offer no confirmation of its existence. Therefore, the hypothesis of Ilkhanid construction relies solely on archaeological evidence and the dated inscription of the Aq-Qalih Mosque. This research seeks to establish the significance of Aq-Qalih as a midway settlement along Ilkhanid travel routes in northern Khorasan, utilizing historical documents and GIS analysis. Further, by comparing Aq-Qalih’s structure with contemporaneous structures in Mongol-influenced regions of China and Iran, this study assesses the hypothesis of Ilkhanid construction. The findings indicate Aq-Qalih’s strategic location along major Ilkhanid travel routes, with the Ilkhans’ and their successors’ annual visits increasing the likelihood of a midway settlement. Moreover, structural comparisons with Chinese examples like Shangdu, Daidu, and Yingchang, as well as Sultaniyya in Iran, reveal significant similarities, bolstering the hypothesis of Ilkhanid-era construction.