Unrestricted Submarine Warfare

In 1897 Alfred von Tirpitz was appointed state secretary of state of the Imperial German Navy. He was responsible for the massive increase in the size of the German navy. Tirpitz wanted a fleet to challenge British supremacy of the seas. He declared that Germany must be prepared for "a battle in the North Sea against England". In 1911 he was granted the title of Grand Admiral.

After war was declared in 1914, Tirpitz urged a policy of unrestricted submarine warfare against the British in the Battle of the Atlantic. In the first six months of 1915, German U-Boats sank almost 750,000 tons of British shipping. The introduction of the convoy system in 1916 helped to reduce the scale of this loss.

Primary Sources

(1) General Paul von Hindenburg, Out of My Life (1934)

On the other hand, in view of England's economic situation, the Imperial Admiralty promises us that by the ruthless employment of an increased number of U-boats we shall obtain a speedy victory, which will compel our principal enemy, England, to turn to thoughts of peace in a few months. For that reason, the German General Staff is bound to adopt unrestricted U-boat warfare as one of its war measures, because among other things it will relieve the situation on the Somme front by diminishing the imports of munitions and bring the futility of the Entente's efforts at this point plainly before their eyes. Finally, we could not remain idle spectators while England, realising all the difficulties with which she has to contend, makes the fullest possible use of neutral Powers in order to improve her military and economic situation to our disadvantage.

(2) Alfred von Tirpitz, My Memoirs (1919)

Two lines of thought were emerging at that time (late 1890s): the tactical necessity for a battlefleet, if we were striving for sea-power and wanted to build ships to some purpose; and the political necessity of establishing a protecting navy for Germany's maritime interests which were growing at such an irresistible pace. The navy never seemed to me to be an end in itself but always a function of these maritime interests. Without sea-power Germany's position in the world resembled a mollusc without a shell. The flag had to follow trade, as other older states had realized long before it

began to dawn upon us.

The 'Open Door,' which could easily be closed, was to us what their broad plains and inexhaustible natural wealth were to the other Powers. This, combined with our hemmed-in and dangerous continental position, strengthened me in my conviction that no time was to be lost in beginning the attempt to constitute ourselves a sea-power. For only a fleet which represented alliance-value to other great Powers, in other words a competent battle fleet, could put into the hand of our diplomats the tool which, if used to good purpose, could supplement our power on land.

It was, and is, an illusion, however, to think that the English would have treated us any better, and have allowed our economic growth to have proceeded unchecked if we had had no fleet. They would have certainly told us to stop much sooner.

(3) Kaiser Wilhelm II issued orders to U-boat commanders on 1st February, 1917.

We will frighten the British flag off the face of the waters and starve the British people until they, who have refused peace, will kneel and plead for it.

(4) The British government began a poster campaign in 1917 in an effort to persuade people to save food.

I am the crust. When you throw me away or waste me you are adding twenty submarines to the German Navy. Save me and I will save you.

(5) President Woodrow Wilson, speech (1st February, 1917)

I have called the Congress into extraordinary session because there are serious, very serious, choices of policy to be made, and made immediately, which it was neither right nor constitutionally permissible that I should assume the responsibility of making.

On the 3rd of February last, I officially laid before you the extraordinary announcement of the Imperial German government that on and after the 1st day of February it was its purpose to put aside all restraints of law or of humanity and use its submarines to sink every vessel that sought to approach either the ports of Great Britain and Ireland or the western coasts of Europe or any of the ports controlled by the enemies of Germany within the Mediterranean.

That had seemed to be the object of the German submarine warfare earlier in the war, but since April of last year the Imperial government had somewhat restrained the commanders of its undersea craft in conformity with its promise then given to us that passenger boats should not be sunk and that due warning would be given to all other vessels which its submarines might seek to destroy, when no resistance was offered or escape attempted, and care taken that their crews were given at least a fair chance to save their lives in their open boats. The precautions taken were meager and haphazard enough, as was proved in distressing instance after instance in the progress of the cruel and unmanly business, but a certain degree of restraint was observed.

The new policy has swept every restriction aside. Vessels of every kind, whatever their flag, their character, their cargo, their destination, their errand, have been ruthlessly sent to the bottom without warning and without thought of help or mercy for those on board, the vessels of friendly neutrals along with those of belligerents. Even hospital ships and ships carrying relief to the sorely bereaved and stricken people of Belgium, though the latter were provided with safe conduct through the proscribed areas by the German government itself and were distinguished by unmistakable marks of identity, have been sunk with the same reckless lack of compassion or of principle.

International law had its origin in the attempt to set up some law which would be respected and observed upon the seas, where no nation had right of dominion and where lay the free highways of the world. By painful stage after stage has that law been built up, with meager enough results, indeed, after all was accomplished that could be accomplished, but always with a clear view, at least, of what the heart and conscience of mankind demanded.

This minimum of right the German government has swept aside under the plea of retaliation and necessity and because it had no weapons which it could use at sea except these which it is impossible to employ as it is employing them without throwing to the winds all scruples of humanity or of respect for the understandings that were supposed to underlie the intercourse of the world. I am not now thinking of the loss of property involved, immense and serious as that is, but only of the wanton and wholesale destruction of the lives of noncombatants, men, women, and children, engaged in pursuits which have always, even in the darkest periods of modern history, been deemed innocent and legitimate. Property can be paid for; the lives of peaceful and innocent people cannot be.

The present German submarine warfare against commerce is a warfare against man- kind. It is a war against all nations. American ships have been sunk, American lives taken in ways which it has stirred us very deeply to learn of; but the ships and people of other neutral and friendly nations have been sunk and overwhelmed in the waters in the same way. There has been no discrimination. The challenge is to all mankind.

With a profound sense of the solemn and even tragical character of the step I am taking and of the grave responsibilities which it involves, but in unhesitating obedience to what I deem my constitutional duty, I advise that the Congress declare the recent course of the Imperial German government to be in fact nothing less than war against the government and people of the United States; that it formally accept the status of belligerent which has thus been thrust upon it; and that it take immediate steps, not only to put the country in a more thorough state of defense but also to exert all its power and employ all its resources to bring the government of the German Empire to terms and end the war.

(6) President Woodrow Wilson, speech (3rd April 1917)

The new policy, however, has swept every restriction aside. All vessels, irrespective of cargo and flag, have been sent to the bottom, without help and without mercy. Even hospital and relief ships, though provided with the Germans' safe conduct, were sunk with the same reckless lack of compassion or principle.

Germany's submarine warfare is no longer directed against belligerents, but against the whole world. All nations are involved in Germany's action. The challenge is to all mankind. Wanton, wholesale destruction has been effected against women and children while they have been engaged in pursuits which even in the darkest periods of modern history have been regarded as innocent and legitimate.

There is one choice I cannot make. I will not choose the path of submission, and suffer the most sacred rights of the nation and of the people to be ignored and violated.

With a profound sense of the solemn and even tragic character of the step I am taking, and of the grave responsibilities involved, but in unhesitating obedience to my constitutional duty, I advise Congress to declare that the recent course of the German Government is nothing less than war against the United States, and that the United States accept the status of a belligerent which has been thrust upon it, and will take immediate steps to put the country into a thorough state of defence, and to exert all her power and resource in bringing Germany to terms, and in ending the war.