Extended submarine warfare begins

The British chronology of the war records under 1 March 1916 the beginning of the extended German submarine campaign. The orders of which Berlin had notified the neutral states in February came into force a day earlier, on 29 February, and the Germans refused to postpone them despite Washington’s requests. From then on the commanders of German submarines could attack Entente merchant ships armed with guns without warning, as if they were warships. Passenger ships, even armed ones, were for the time being to be spared.

Half a step instead of a whole one

The extended campaign was a compromise. The navy wanted much more. At conferences at the Prussian War Ministry on 30 December 1915 and 5 January 1916, the Chief of the Admiralty Staff, Henning von Holtzendorff, called unrestricted submarine warfare the salvation of the fleet and proposed starting it on precisely 1 March. A memorandum of his staff dated 7 January asserted that once all restrictions were lifted Britain’s resistance would be broken within six months at the latest. This was supported by the State Secretary of the Navy, Alfred von Tirpitz, and by the Chief of the General Staff, Erich von Falkenhayn, who was already preparing the attack at Verdun and believed that Britain could not be defeated on land.

The Chancellor, Theobald von Bethmann Hollweg, however, feared war with the United States and won a delay. According to the British official naval history, the submarines were from then on to wage commerce warfare “according to the rules of prize law”, that is, to stop and search ships, and to sink without warning only armed merchant ships and transports. Passenger ships were not to be attacked under any circumstances. More and more British merchant ships sailed with a gun on the stern, so the new rules covered an ever larger part of the merchant fleet. In practice everything depended on how a submarine commander, looking through the periscope, judged the ship he encountered.

At sea

The submarines had returned to their old hunting grounds off the west coast of Britain as early as the second half of February. According to the British official history they operated there in pairs and within four weeks sank ships totalling about 35,000 tons in those waters, and damaged several more. In the English Channel and off the Flemish coast small boats of the Flanders Flotilla were hunting. Ships of neutral states also fell victim. On 16 March the large Dutch liner Tubantia, bound from Amsterdam for Buenos Aires, sank near the Noord Hinder lightship. Everyone on board was saved, but the Dutch were outraged, and the Germans long denied that it had been sunk by their torpedo. According to later findings it was torpedoed by UB-13.

The dispute goes on

In Washington, President Woodrow Wilson in the first week of March pushed through Congress the rejection of the resolutions calling on Americans to avoid armed ships. The United States thus did not accept the new German rules and announced that it would hold Berlin responsible for the deaths of its citizens on a ship armed for defence.

In Germany the advocates of unrestricted submarine warfare did not give up. According to Tirpitz’s memoirs, the further course was decided on 6 March at a conference with Kaiser Wilhelm II attended by the Chancellor, Falkenhayn and Holtzendorff. The Kaiser, against Falkenhayn, postponed unrestricted submarine warfare indefinitely. Tirpitz, who had not been summoned to the conference, was soon replaced by Admiral Eduard von Capelle. The British official history states that in return for the postponement the Chancellor had to agree to a further tightening of the orders: in the war zone around the British Isles all enemy ships except passenger ships could from then on be attacked without warning. The line between a passenger ship and any other, however, proved easy for submarine commanders to cross, which by the end of March had led to a new crisis in relations with the United States.