Owing to the peculiar nature and demands of naval warfare, but few dispatches, corresponding to those describing the work and achievements of our great armies, were issued during the progress of the war. In a former volume I attempted to supply this defect in the historical records, which will be available for future generations, so far as the Grand Fleet was concerned, during my period as its Commander-in-Chief. The present volume, which was commenced and nearly completed in 1918, was to have been published at the same time. My departure on a Naval mission early in 1919 prevented me, however, from putting the finishing touches to the manuscript until my return this spring.

I hesitated as to the publication of this portion of what is in effect one complete narrative, but eventually decided not to depart from my original purpose. There is some reason to believe that the account of the work of the Grand Fleet gave the nation a fuller conception of the services which the officers and men of that force rendered in circumstances which were necessarily not easily appreciated by landsmen.

This second volume, dealing with the defeat of the enemy's submarine campaign, the gravest peril which ever threatened the population of this country, as well as of the whole Empire, may not be unwelcome as a statement of facts. They have been set down in order that the sequence and significance of events may be understood, and that the nation may appreciate the debt which it owes, in particular, to the seamen of the Royal Navy and the Mercantile Marine, who kept the seas during the unforgettable days of the intensive campaign.

This book, therefore, gives the outline of the work accomplished by the Navy in combating the unrestricted submarine warfare instituted by the Central Powers in February, 1917. It would have been a labour of love to tell at greater length and in more detail how the menace was gradually overcome by the gallantry, endurance and strenuous work of those serving afloat in ships flying the White or the Red Ensigns, but I had not the necessary materials at my disposal for such an exhaustive record.

The volume is consequently largely concerned with the successive steps taken at the Admiralty to deal with a situation which was always serious, and which at times assumed a very grave aspect. The ultimate result of all Naval warfare must naturally rest with those who are serving afloat, but it is only just to the Naval officers and others who did such fine work at the Admiralty in preparing for the sea effort, that their share in the Navy's final triumph should be known. The writing of this book appeared also to be the only way in which I could show my keen appreciation of the loyalty and devotion to duty of the Naval Staff, of the many clever, ingenious and audacious schemes developed and carried through for the destruction of submarines and the safeguarding of ocean-borne trade, and of the skilful organization which brought into being, and managed with such success, that great network of convoys by which the sea communications of the Allies were kept open. The volume shows how the officers who accompanied me to the Admiralty from the Grand Fleet at the end of 1916, in association with those already serving in Whitehall and others who joined in 1917, with the necessary and valuable assistance of our comrades of the Mercantile Marine, gradually produced the measures by which the Sea Service conquered the gravest danger which has ever faced the Empire.

There were at times inevitable set-backs as the enemy gained experience of our methods, and new ones had then to be devised, and we were always most seriously handicapped by the strain imposed upon the Fleet by our numerous military and other commitments overseas, and by the difficulty of obtaining supplies of material, owing to the pre-occupation of our industries in meeting the needs of our Armies in equipment and munitions; but, generally speaking, it may be said that in April, 1917, the losses reached their maximum, and that from the following month and onwards the battle was being slowly but gradually won. By the end of the year it was becoming apparent that success was assured.

The volume describes the changes carried out in the Admiralty Staff organization; the position of affairs in regard to submarine warfare in the early part of 1917; and the numerous anti-submarine measures which were devised and brought into operation during the year. The introduction and working of the convoy system is also dealt with. The entry of the United States of America into the war marked the opening of a new phase of the operations by sea, and it has been a pleasure to give particulars of our cordial co-operation with the United States Navy. The splendid work of the patrol craft and minesweepers is described all too briefly, and I have had to be content to give only a brief summary of the great services of the Dover and Harwich forces.

Finally, an effort has been made to suggest the range and character of the work of the Production Departments at the Admiralty. It is impossible to tell this part of the story without conveying some suggestion of criticism since the output never satisfied our requirements. I have endeavoured also to indicate where it seemed to me that changes in organization were not justified by results, so that in future years we may benefit by the experience gained. But I would not like it to be thought that I did not, and do not, realize the difficulties which handicapped production, or that I did not appreciate to the full the work done by all concerned.

It is unfortunate that attempts to draw attention to the lessons taught us by the war are regarded by many people either as complaints of lack of devotion to the country's interests on the part of some, or as criticisms of others who, in the years before the war or during the war, were responsible for the administration of the Navy. In anticipation of such an attitude, I wish to state emphatically that, where mention is made of apparent shortcomings or of action which, judged by results, did not seem, to meet a particular situation, this is done solely in order that on any future occasion of a similar character—and may the day be long postponed—the nation may profit by experience.

Those who are inclined to indulge in criticism should ever bear in mind that the Navy was faced with problems which were never foreseen, and could not have been foreseen, by anyone in this country. Who, for instance, would have ever had the temerity to predict that the Navy, confronted by the second greatest Naval Power in the world, would be called upon to maintain free communications across the Channel for many months until the months became years, in face of the naval forces of the enemy established on the Belgian coast, passing millions of men across in safety, as well as vast quantities of stores and munitions? Who would have prophesied that the Navy would have to safeguard the passage of hundreds of thousands of troops from the Dominions to Europe, as well as the movement of tens of thousands of labourers from China and elsewhere? Or who, moreover, would have been believed had he stated that the Navy would be required to keep open the sea communications of huge armies in Macedonia, Egypt, Palestine, Mesopotamia and East Africa, against attack by surface vessels, submarines and mines, whilst at the same time protecting the merchant shipping of ourselves, our Allies, and neutral Powers against similar perils, and assisting to ensure the safety of the troops of the United States when they, in due course, were brought across the Atlantic? Compare those varied tasks with the comparatively modest duties which in pre-war days were generally assigned to the Navy, and it will be seen how much there may be to learn of the lessons of experience, and how sparing we should be of criticism. Wisdom distilled from events which were unforeseeable should find expression not in criticisms of those who did their duty to the best of their ability, but in the taking of wise precautions for the future.

Little mention is made in this volume of the work of the Grand Fleet during the year 1917, but, although that Fleet had no opportunity of showing its fighting power, it must never be forgotten that without the Grand Fleet, under the distinguished officer who succeeded me as Commander-in-Chief at the end of 1916, all effort would have been of no avail, since every operation by sea, as well as by land, was carried out under the sure protecting shield of that Fleet, which the enemy could not face.

I am conscious of many shortcomings in the book, but it may prove of interest to those who desire to know something of the measures which gradually wore down the German submarine effort, and, at any rate, it is the only record likely to be available in the near future of the work of fighting the submarines in 1917.

June, 1920.