This article focuses on the military expedition of Orenburg and Samara Governor-General V. A. Perovsky against important Kokand fortress AK-Mosque that stood by the river Syrdarya in 1853, which resulted in the capture of the Kokand fortresses and the stabilization of the situation in the Central Asian caravan routes in the middle of the XIX century. The article also presents the causes and preconditions of operation, determined by the historical significance of this campaign, which became part of the prehistory of the large-scale seizure of Central Asia by the Russian Empire in the second half of the XIX century, based, among other things, on unpublished archival sources.