Submarines and naval layered defence in the first world war

Abstract

This dissertation provides an entirely new understanding of British submarine policy and Royal Navy submarine operations during the First World War. British submarines operating in the North Sea were an enabling technology that freed the different surface warship types to be used to achieve their full potential. The Admiralty was thus able to implement flexible layered defence systems that were developed and modified to meet the changing strategic demands. The immediate prewar commissioning of overseas type submarines capable of conducting an observational blockade off the German North Sea littoral relieved the dangerous need for surface warships to operate such a blockade. These submarines provided a solution to the “North Sea Problem” that had been causing such great concern to the Admiralty. This rather than secret and unwritten plans to defend Britain by so-called ‘flotilla defence’ drove British submarine policy. During the war, the Admiralty was very quick to identify new operational requirements and new submarines were designed and built to provide specialist capabilities. The infrastructure to support submarine operations was also established with fixed bases and mobile depot ships. Submarines were integrated with surface warships in mutually supporting layers. In addition to the observational roles, the fleet submarines were to accompany the Grand Fleet, and in a fleet action to manoeuvre to attack the High Seas Fleet on its disengaged side. Minelaying submarines penetrated deep into the Heligoland Bight to positions inaccessible to surface minelayers. In anti-U Boat warfare, submarines were positioned in layered patrol areas integrated with surface warships. Weapon systems and equipment were also developed rapidly that expanded submarine capabilities. Postwar layered defence systems continued to be enhanced with new naval technologies and new strategic requirements, and they are still relevant today.