This book is the first publication in several decades of essays from "Historical Monographs and Studies" and other works by N.I. Kostomarov. Our publication returns several historical and literary works to the general reader. These are "The Personality of Tsar Ivan Vasilyevich the Terrible," "0 investigation into the murder of Tsarevich Dimitri," "Tsarevich Alexey Petrovich" and others. The works are devoted to the events of Russian history of the XVI-XVIII centuries, which still cause acute interest and controversy. For everyone interested in Russian history.