He completed his PhD in 1942 in the same department. His PhD thesis was on the Bulgarian question in the late Ottoman Empire, specifically during tanzimat, and constituted one of the first socioeconomic approaches in Turkish historiography. In December 1943, he became assistant professor and his research interest became focused on the social and economic aspects of the Ottoman Empire.
He completed his PhD in 1942 from the same academic division. His dissertation examined the Bulgarian issue within the late Ottoman Empire's tanzimat period, embodying one of the first socioeconomic viewpoints in Turkish historiography. In December 1943, he became an assistant professor and redirected his research focus toward the social and economic facets of the Ottoman Empire.