The book is dedicated to the combat operations of British B-type submarines during the First World War, the centenary of which is not much time left. Based on English and German sources, the operations of E-class submarines in the two most important theaters of war (TVD) are described in detail - the northern and Mediterranean, and in each of them the operational stress coefficient was quite high. Considerable attention is paid to the actions of English boats during the crossing of the Dardanelles by the Anglo-French fleet. Along with the technical aspects, military-political, diplomatic and other subjects related to the actions of the member states of the Entente bloc and their main rivals - Germany and Turkey during the war are considered. For a wide range of readers interested in naval history.