The Weapon That Almost Won the Kaiser the War

A look at die Unterseebooten (U-Boats) that were a major problem for the Merchant Navy and the RN during the 1914-1918 War.

From The Mad Monarchist (5 March 2016)

When most think of German submarine achievements, they think of World War II with the Battle of the Atlantic, the great “aces” like Kretschmer, Topp, Schepke, Prien and so on and the famous words of Winston Churchill who said that the u-boat menace was the only thing that made him worry Britain might lose the war. However, while the German submarine fleet of World War II was larger and faced a more experienced foe, it was the u-boats of the Imperial German Navy in World War I that set most of the records, that developed the first weapons which the most successful of World War II were built upon, where the tricks of the trade were first developed and the Kaiser’s u-boats actually came much closer than most people realize to winning the First World War all on their own. This is all the more remarkable considering that, at the outset of World War I, not many people saw the submarine as possessing much potential. The leadership of the German High Seas Fleet tended to look down on submarines as being of little practical value and at the start of the war Germany actually possessed far fewer submarines than the British did. The Germans had never shown much interest in submarines compared to the Americans, French, British or Italians. However, it was the Kaiser’s submarines who would show the world, for the first time, what submarines were capable of.

Otto Hersing

At the start of the war, doubts about the viability of the u-boats seemed to be confirmed. The early models were all small, coastal boats which handled poorly and were driven by kerosene-powered engines that produced a telltale column of smoke that made them easy to spot. The first boats to be equipped with diesel engines were also so innovative that they were initially fairly unreliable as they were still working the bugs out. Their first war patrols were a complete failure, some being forced to return to port with engine trouble, one being sunk and none having any success against the British. The naysayers, which included Grand Admiral Tirpitz, seemed to have been proven right. However, they soon had reason to doubt that assumption when, on September 5, 1914, U-21 under the command of Oberleutnant zur See Otto Hersing became the first submariner to sink an enemy warship with a free-swimming torpedo when he successfully attacked the British cruiser HMS Pathfinder, sending her to the bottom with a single torpedo that hit near the magazine causing a massive explosion that quickly sent the ship plunging beneath the waves. This got some attention but many could still dismiss it as a lucky shot.

However, the next victory for the u-boats would be so spectacular that everyone, in Britain and Germany, had to start taking them more seriously. That same month, on September 22, Oberleutnant zur See Otto Weddigen in the elderly, kerosene-powered U-9, encountered three British cruisers off the Dutch coast. He had spent the night on the bottom, to give his men a break from the heavy seas and his batteries were not fully recharged when he encountered the enemy but he submerged his boat and prepared for an underwater attack. After moving in to a hair-raisingly close range of 500 meters U-9 hit HMS Aboukir with a single torpedo, sending her to the bottom. The British all assumed the ship had hit a mine and stopped to pick up survivors. Weddigen then targeted HMS Hogue and soon hit her with two torpedoes, sending her to the bottom. However, the sub briefly broke the surface and was spotted by the remaining cruiser, HMS Cressy, which opened fire on the u-boat. However, Weddigen turned his boat around and fired the two torpedoes from his stern tubes. These were spotted by the British, but U-9 was so close that there was no time to avoid them and HMS Cressy was mortally wounded. Weddigen then brought his boat around to finish off the enemy cruiser with his remaining torpedo after which he returned to port to reload. He and his crew of the U-9 had sunk three British cruisers in less than an hour!

Captain & crew of the U-9

Upon returning to Germany, the men of the U-9 were bona fide war heroes. The Kaiser was thrilled and every member of the crew was decorated with the Iron Cross, Second Class and Weddigen additionally received the Iron Cross First Class. The U-9 itself was given the honor of displaying the Iron Cross on its conning tower. In the second month of the war the submarine had just proven itself in a major way and no one would be quite so dismissive of them again. In addition, more success was on the way and both Hersing and Weddigen were well on their way to becoming two of the most celebrated submarine commanders of the war. And, although anti-submarine warfare was necessarily in its infancy, they faced a powerful enemy with the largest fleet in the world and in these early days of the war it was the Royal Navy that was the primary target of the German submarines rather than the merchant fleet. In October of 1914 the U-26 under Kapitanleutnant von Berckheim sank a Russian cruiser, the Pallada, followed, a few days later, by Otto Weddigen taking out yet another British cruiser, HMS Hawke.

Johannes Feldkirchener

The British, having denied the problem as long as possible, were suddenly thrown into a panic, sending out new orders, rerouting ships and even moving the home fleet from their anchorage in Scapa Flow until it could be fortified against submarine attack. On October 18, 1914 Kapitanleutnant Wegener in U-27 became the first submariner to sink an enemy submarine when he took out the British boat E-3. Two days later U-17 became the first sub to sink an enemy merchant ship when the freighter Glitra was stopped, inspected, had her crew off-loaded and was then sent to the bottom. November was less successful for the u-boats with more being lost but as the year ended the submarine had more than proven its worth and more Germans began to believe that it could be the key to defeating the Royal Navy. The sinking of the Glitra was also a pivotal event. With the British enforcing an ever tighter blockade of the entire North Sea, the Germans began to think of changing their strategy of submarine warfare to target merchant ships bound for the British Isles rather than Royal Navy warships.

U-24

Still, British overconfidence allowed the Germans to score some stunning victories. At the start of January, 1915 HMS Formidable, sailing with no escort destroyers, was sunk by U-24. The British responded with more patrol ships, wider use of anti-submarine nets and by laying more mines in areas u-boats had to cross through. At the time, there was little more they could do as this was before the use of underwater search gear or weapons such as the depth charge. For a British surface vessel, if you spotted a sub on the surface you shot at it of course and if you spotted a periscope you charged it, ramming the submarine and ripping it in half. Ships were also ordered to sail in a zigzag pattern and to show extra caution when traveling near waters where u-boats were most likely to be on the prowl. These measures were actually fairly effective and of all the German u-boats lost in action in World War I the majority were victims of mines and the Royal Navy did their best to lay belts of mines across the English Channel as well as the northern entrance to the North Sea, from Scotland to Norway, to bottle-up the u-boat menace.

Kaiser Wilhelm II

February of 1915, however, saw the German submarines adopting the new strategy of targeting the British merchant fleet rather than the Royal Navy. Kaiser Wilhelm II declared all the waters around the British Isles to be a war zone, effectively declaring a counter-blockade to match the British blockade of the North Sea. The Germans were also able to make use of ports in Belgium for their submarine fleet. During the war the Imperial German Navy maintained five u-boat and one u-cruiser flotillas in Germany itself, two u-boat flotillas in Flanders operating from Belgian ports, two u-boat flotillas in the Mediterranean operating from Austrian ports and one half-flotilla in Turkish waters operating out of Constantinople. As the German subs embarked on their first campaign against merchant shipping they also had several new, larger and more powerful sub types to work with. In February 1915, eight merchant ships were sunk, five by U-8 alone. In March there were 29 sunk, in April 33 and in May 53 with several warships being sunk as well during that time. The Germans also began their own mine laying operations with the UC-type submarines, particularly in the waters around France.

Walther Schwieger

However, there were also problems. In May of 1915 the U-20 under Kapitanleutnant Walter Schwieger torpedoes the British passenger liner RMS Lusitania off the coast of Ireland. 1,201 passengers were killed, including 128 Americans which caused an uproar in the United States against Germany, something the British took full advantage of in their propaganda even though the ship had been carrying war materials and was thus a legitimate target. The German high command was forced by political pressure to order submarines not to attack neutral ships or passenger ships even if they were under the flag of a country at war with Germany. Nonetheless, the u-boats still proved highly effective and in the next four months 365 merchant ships were lost to submarine attacks. If u-boat successes of that scale continued they would soon be sinking ships faster than the British could replace them and Britain would be forced to sue for peace or face starvation of both her populace and her war industries. However, in due time two more passenger liners were sunk, one of which again had American passengers and another which was sunk by Walter Schwieger, making him quite a hated figure among the Allies and their sympathizers. The outcry from the United States forced the German high command to pull back and order all u-boats to operate strictly in accordance with the rules which stated that a ship had to be stopped, inspected and the crew offloaded before being sunk.

Germans sang the praises of the submarine

This, of course, deprived the submarine of the element of surprise and forced them to surface where they were most vulnerable. Even an unarmed freighter could ram and sink a u-boat and the British also began using “Q-ships” which were disguised as harmless merchant vessels but carried hidden guns. When a u-boat surfaced to stop the ship and inspect the cargo for war materials, the guns would be revealed and open fire on the vulnerable submarine. As a result, when these rules were in place, the German u-boats were forced to, effectively, fight with one hand tied behind their backs. Nonetheless, 1915 also saw the expansion of the submarine campaign into the Mediterranean where French, Austrian, Italian and British submarines also operated. Germany was to obtain some of her greatest submarine successes in this theater of the naval war. Yet, as 1915 came to a close and 1916 opened, the naval situation was becoming increasingly critical for Germany.

Erich von Falkenhayn

The British blockade of the North Sea was stopping at least three times as much shipping to Germany as the German submarine cordon was stopping from reaching Britain. The people were beginning to suffer greatly and more and more important figures in the German military high command were urging the Kaiser to throw off the shackles and resume unrestricted submarine warfare with a ‘sink on sight’ policy regardless of the objections of neutral powers (especially the United States). The German army Chief of Staff, Colonel General Erich von Falkenhayn, urged for such a campaign to coincide with his massive offensive aimed at Verdun in the hope that, together, they could crush the Allied will to continue the struggle and force them to make peace on German terms. The politicians, however, warned the Kaiser that such a move could bring the United States into the conflict and with such overwhelming might arrayed against them, Germany would surely be doomed. As a result, the Kaiser approved the Verdun offensive but refused to remove all of the restrictions for the submarine campaign. Admiral Tirpitz, the man who had once said Germany had no need of submarines, was so upset by the decision that he resigned in protest.

on the hunt

Still, the German u-boats started their 1916 campaign with some success, both with coastal boats and mine-laying subs. However, after a passenger ship was mistaken for a troop carrier and sunk on March 24, 1916 by the coastal sub UB-29 there was such an outcry, with U.S. President Wilson threatening to break off diplomatic relations with Germany (usually a precursor to war) that the Kaiser was forced to cancel even the limited leeway he had allowed his submarine commanders and order them to strictly follow the traditional prize rules. This was all the more infuriating given that the British were steadily improving their anti-submarine tactics and their “Q-ships” had already sent a number of u-boats to a watery grave. One such vessel, the Barralong, even hunted down and massacred all the surviving sailors of one such hapless u-boat on the grounds that if the Germans were allowed to live they would report the incident to their superiors and the British deception would be revealed. German losses mounted with one boat, UC-5, even being captured intact after running aground. Still, the u-boats managed to sink over 150 ships in 1916 before Admiral Scheer ordered them all to return to base on April 25.

UB-148

The following month a new plan was approved that would see the u-boats return to taking on their original enemy; British warships. The idea was for a portion of the German High Seas Fleet to lure out their British counterparts into a death trap of mines and waiting submarines. It seemed like a good plan but delays and mechanical trouble foiled the first attempt to put the plan into effect and the second attempt, in August, likewise did not go as planned and resulted in the Battle of Jutland, the only major clash of the British and German main fleets during the war. The only contribution by the German submarines was the sinking of two light cruisers. These frustrations, combined with the increasing privation of the German people caused by the British blockade put pressure on the Kaiser to authorize a return to unrestricted submarine warfare for a renewed campaign against British merchant shipping in an effort to starve them into submission.

However, the threat of American intervention proved too great so that, while another submarine campaign against merchant shipping was authorized, it would have to be done under the restrictions of the traditional prize rules. It was a disappointment but still, there were victories to be had as within four months 290 merchant ships were lost to u-boat attacks. The Germans also had an increasingly diverse arsenal of boats at their disposal with small, coastal submarines to hunt in waters closer to home (such as the Channel), medium-sized boats that could prowl all around the British Isles and even larger submarines that could hunt as far away as the U.S. coast. U-41, for example, sent five ships to the bottom off the American coast during this campaign. The type-UBIII proved the most successful and would be the forerunner of the type-VII that would be the backbone of the German u-boat fleet in World War II.

Lothar von Arnauld

Along with the Atlantic and British coastal waters, the Mediterranean also proved to be a fertile hunting ground. It was there that the most successful submarine commander of all time, Kapitanleutnant Lothar von Arnauld de la Periere, achieved his greatest victories. In one cruise, lasting three weeks, he sank more than fifty ships, mostly with his deck gun (he expended only four torpedoes during the voyage) as he very gallantly followed all the prize rules even when he was not obliged to. Before the war ended, Kptlt. Lothar von Arnauld de la Periere would sink almost half a million tons of Allied shipping. They also had an impact on the land war as, in 1915, Kptlt. Otto Hersing in U-21 sank two British battleships, under extremely difficult conditions, which were shelling Turkish positions during the Gallipoli campaign. This stunning loss forced the Royal Navy to withdraw most warships from the area, robbing the Allied troops of valuable fire support in their offensive. Ten German subs were lost during the 1916 campaign but they managed to sink 768 ships with a further 178 being badly damaged. This, along with the worsening situation on the home front and the rejection by the Allies of an offer to talk peace, added urgency to calls for resuming unrestricted submarine warfare. After all, if they could accomplish this with the restrictions on their boats, surely without them they could swiftly force Britain to capitulate.

Max Valentiner

With the war situation becoming more and more critical, Kaiser Wilhelm II finally felt he had no other choice but to re-authorize unrestricted submarine warfare in February of 1917. Everyone knew it would likely provoke the United States to enter the war but with Germany rapidly running out of manpower and the public approaching widespread death by starvation, that was a risk that would simply have to be taken. Once the “grey wolves” were unleashed, the results were dramatic and immediate. Before the month of February 1917 was out German submarines had sunk over 250 ships, in March over 300 were sunk and April saw 413 ships sent to the bottom. British imports had been reduced by 75% of what they had been in 1916, shipyards were swamped and many neutrals refused to risk entering British waters. British ports were likewise clogged with merchant ships that refused to put back out to sea for fear of being sunk by German u-boats. The Kaiser’s naval experts had predicted that their campaign would bring Britain to her knees within six months, by the halfway mark, it looked like they were well on their way to doing just that. German u-boat production was also increasing so that they were more than able to make up their own losses. However, as feared, this campaign had consequences and April of 1917 also saw the United States declare war on Germany after an ill-advised German effort was uncovered to induce Mexico to make war on America.

Walther Forstmann

It would be some time, of course, before American strength would be felt on the battlefield but the British were getting better at anti-submarine warfare against the Germans, with ever more effective minefields, increased use of naval aviation and, most importantly, moving merchant ships in convoys protected by destroyers that forced u-boats to attack on the surface at night. Still, the number of Germans subs lost to enemy action remained well within the capacity of Germany to replace them. Nonetheless, British countermeasures were improving. The Germans also had a slight disadvantage just in terms of bad timing. They had developed large, long-range “u-cruisers” that carried heavy deck guns for surface combat and these became available just when unrestricted submarine warfare was revived and thus there was no great need for resorting to surface action or for the extra personnel these boats carried as prize crews for captured ships. The German submariners were also only improving with time, becoming masters of their craft and from May to July of 1917 some 795 merchant ships were lost to them compared to only minor losses of their own. For comparison, the Germans sank about 50 ships for every one of their u-boats lost to enemy action.

Otto Weddigen

The u-boats were tantalizingly close to their goal and yet that goal was slipping away from them, particularly as the industrial output of the United States was thrown into the balance against them with all of the ships of the American merchant marine and their immense capacity for building more. In desperation, the Germans drastically increased the construction of new submarines, funneling as much of their dwindling resources as possible into the project with 95 new boats on order. Hunting also shifted from the Atlantic to coastal waters but this also coincided with increasing losses as the British massively increased their use of naval mines and were making better mines than ever before. These weapons took the heaviest toll of all on the German u-boat fleet. As 1917 gave way to 1918 these trends continued and soon submarine construction was barely able to keep up with the rate of attrition. The Allies had managed to gain the upper hand and were to keep it until the end of the war came in November. From January to November of 1918 shipping losses to German u-boats fell from 123 to 15.

running on top

In spite of this downward trend, German successes had cemented the submarine as the most feared weapon in the minds of the Allies and when the Germans first approached the Americans about ending hostilities (the terms proposed by America being much more lenient compared to those of the British or French) the first condition the Americans imposed was that submarine attacks must cease immediately before any talks could be held. As a result, on October 20, 1918 the German high command ordered all u-boats to return to port. The German navy planned, instead, on a final battle with their surface ships, planning to go down in a blaze of glory rather than surrender their ships to the Allies. However, this never happened as the German sailors, some of them infected by communist propaganda from Russia, mutinied, the first act of what would grow to be the German Revolution that brought down the Second Reich and all its subsidiary monarchies. It is worth noting, however, that the German u-boat crews remained loyal to their Kaiser to the bitter end and were even ordered to fire on any German ship flying the revolutionary flag, such was their reliability.

U-35

When World War I finally came to an end, Germany still possessed quite a large number of submarines. They had, after all, never been defeated outright on their own and over 170 u-boats remained ready for action when hostilities ended. Which is not to say they did not suffer losses of course. Of the 350 submarines Imperial Germany produced during the war, about 180 were lost in action and of the 13,000 sailors who served on the u-boats 5,354 were killed in action. Nonetheless, they had given incredible service and deserve to be recognized for it even as their World War II counterparts tend to receive more attention. In fact, of the top ten German submarine commanders of all time, six were sub captains of the Imperial Navy in World War I including the top three most successful sub commanders in the entire history of naval warfare; Kptlt. Lothar von Arnauld de la Periere, Kptlt. Walther Forstmann and Kptlt. Max Valentiner. Overall, the Kaiser’s submarines had destroyed more than 11 million tons of Allied shipping during the war and damaged a further 7.5 million tons, an incredible achievement if ever there was one.

cheering U-Boat crew in 1916

Yet, even given that the Imperial German u-boats had done so much damage, even though the Imperial German submarine commanders outperformed all others (in the world), many still do not know just how close they came to winning the war for Germany. While historians tend to focus on things like the First Battle of the Marne or Operation Michel (and the Second Battle of the Marne) and so on, the German u-boats were the key element that came closer to winning the war than any of them. To understand this, one need only look at the situation in April of 1917, just after America entered the war when the German unrestricted u-boat campaign was at its height. Admiral William S. Sims of the U.S. Navy traveled to London to meet with First Lord of the Admiralty Sir John Jellicoe to begin working out the Anglo-American naval relationship and he was shocked to learn just how bad things were for the British. Sims was informed that, at that point, the British had only enough food stocks on hand to last another six weeks!

UB-4, coastal submarine

When German submarine strategists predicted that they could crush Britain with an unrestricted u-boat campaign within six months, that is how close they came to success with Britain a mere six weeks from ruin. Now, keeping that in mind, also consider that for long periods during the war the German submarines were restricted by the prize rules and at times were not hunting merchant ships at all but were focused on engaging the Royal Navy and one can clearly see how the German submarine clearly held the potential to have won the war for the Central Powers practically single-handed. With a total of more than 11 million tons of Allied ships destroyed, think what they could have accomplished if they had focused entirely on merchant shipping from day one and if they had waged unrestricted submarine warfare from the very beginning. The only conclusion is that they would almost certainly have won a swift and stunning victory. Clearly, of all the innovative weapons that emerged from the First World War, none of them came so close to truly changing the course of world history as did the submarine.