In this article, the author examines the concept of “cultural conquest” in the context of the Russian Empire’s policy towards the Caspian provinces of Iran, both prior to and during the Great War. In the period preceding the outbreak of hostilities, Russian peasant colonists began to settle in the Astarabad province, while concurrently, significant Russian land ownership emerged in the southern Caspian region. These developments were subjected to rigorous scrutiny by the Ministry of Foreign Affairs, the Resettlement Department, and other pertinent authorities. The phenomenon is not adequately represented in historiography, despite its significance in the context of New Imperial History. One of the pivotal concepts employed in analysing and comprehending the processes of Russian expansion into the region was the notion of “cultural conquest”. This category was actively employed by both state and non-state actors to conceptualise the ongoing economic, political, and cultural interactions in a crucial frontier region. The analysis of a wide range of materials, including archival and published sources such as diplomatic correspondence, concession projects, and publications by officials from the Resettlement Department, has been conducted with the aim of investigating the contexts of the use of the category “cultural conquest” (and related terms) as well as proposed options for optimal policy in the region. The author indicates that this concept was of a framework nature and comprised three principal components: political, economic, and civilisational. He demonstrates that despite significant similarities in the interpretations of the concept by different actors, there were differences in understanding the methods and optimal ways of “cultural conquest” of the Caspian provinces.