A Naval History of World War I
Page 47
The idea of operations on the Danube was considered in London at the beginning of 1915. It was, like the Dardanelles campaign, attractive to those who favored overseas operations as a means of sidestepping the seemingly endless bloodletting on the western front. At the meeting of the War Council on 13 January 1915, which agreed to Admiral Carden’s plans for reducing the forts at the entrance to the Dardanelles, Lloyd George suggested a major attack on Austria, building rolling stock for the Salonika railway, and perhaps barges for the Danube. Churchill agreed: “At the worst they would be a good feint.”14
Danube operations would have been even more viable after the Dardanelles campaign had been launched, for if the British and French had succeeded in opening the Straits, they would have opened the seaward route to the Black Sea and the Danube. Nevertheless, the War Council of 28 January tacitly accepted Churchill’s opinion that naval force alone would suffice to open the Straits. Any troops available ought to be sent to assist the Serbians via Salonika. The War Council concluded that the Admiralty should order twelve monitors to be built in sections capable of being shipped to Salonika and then sent on to Serbia by rail where they would be assembled for service on the Danube. Lord Fisher promised that next day he would hold a meeting at the Admiralty to begin work on the design for Danube gunboats.15
This was the genesis of the twelve Insect-class gunboats that received the cover name “large China gunboats.” The design called for a 645-ton vessel with propellers running through tunnels to achieve shallow draft. They would have outnumbered and outgunned their potential Austrian rivals with two 6-inch (15.2-cm) guns as opposed to the Austrian’s two 12-cm guns, but unlike the Austrians they had no armor protection and their guns had only open shields rather than being fully enclosed. One historian regards the Austrian craft as much more suited for riverine warfare. The twelve Insect class never served on the Danube during the war, but did excellent work in Mesopotamia.16
Churchill was anxious to have troops on hand to exploit success at the Strait, and at the War Council meeting of 24 February advocated sending the 29th Division to the Near East as soon as possible. When Kitchener objected that the Dardanelles was supposed to be a purely naval venture, Churchill replied that the troops could be sent through the Dardanelles or up to the Bulgarian frontier or possibly to Salonika. If Bulgaria joined the Allies, the troops might go through Bulgaria to Nish or up the Danube. He repeated this proposal on the 26th, but could not win over Kitchener or Lord Balfour, the former prime minister and unofficial representative of the Conservative party in the War Council. Danube operations did gain influential support from Colonel Hankey, secretary of the War Council. Hankey circulated a memorandum, “After the Dardanelles. The Next Steps,” to the council on 2 March. Hankey examined what he considered to be the best means of exploiting a victory at the Dardanelles. He advocated a British advance up the Danube to protect Serbia and as part of an offensive against Austria-Hungary. In this grand scheme, a British force supported by a powerful flotilla would constitute the center of an Allied army. The Serbians and Greeks on the left would move into Bosnia and Herzegovina while the Romanians on the right would form a connecting link with the Russian armies fighting in the Carpathians. The British force would turn the flank of the forces opposing the Romanians, which would enable the latter to threaten the flank of the Austro-Hungarian forces fighting in the Carpathians. The French and British armies on the western front would continue to exert pressure while the hard-pressed Russians on the eastern front, even if forced back, would at least contain enemy forces.17 Hankey’s plan assumed not only a naval victory at the Dardanelles but that neutral Greece and Romania would enter the war.
The failure of the purely naval attack at the Dardanelles on 18 March did not stop consideration of the Danube project. Admiral Henry Jackson produced a memorandum, “Notes on the Transport of Military Forces to Serbia,” dated 25 March, and a memorandum by the hydrographer of the navy, “Report on the River Danube from Budapest to Braila,” was printed at the beginning of April.18 The Admiralty also asked Troubridge for details of tugs, lighters, and suitable and trustworthy agents for hiring them. They wanted information on facilities for disembarking troops at Radujevac and Prahovo—to avoid the difficulties of the rapids at the Iron Gates—as well as the carrying capacity of the railways connecting those towns with the rest of Serbia.19 The War Office cooperated by providing the services of an intelligence officer, Captain L. S. Amery, a member of Parliament and subsequently one of the most influential men in the Conservative party (who would be first lord of the Admiralty, 1922–24). Amery visited likely sites in Serbia and Romania and prepared a detailed report.20
Troubridge was not very encouraging about operations on the Danube. There were no tugs or lighters available in Serbian waters or under Serbian control for the purpose of transport as the Austrians, except for one or two small craft, had destroyed all of the Serbian river craft. Unfortunately the facilities for disembarkation at Prahovo and Radujevac were very primitive and very limited, and it was only with great difficulty that matériel from Russia was disembarked there. The facilities for transporting men and supplies from Radujevac and Prahovo to Parachin on the main rail line were equally limited, and Troubridge doubted they could deal with the requirements of an army. The main Salonika-Nish-Belgrade line was also in poor repair with the whole of the Serbian army living “from hand to mouth” on supplies transported along the railway, and it was not possible to put any further strain on it.
This left the alternative of moving the British forces up the Danube through the Iron Gates and other rapids, but Troubridge did not believe this could be done—even with monitors escorting the troops—until the whole of the left bank, that is, the Hungarian side, was in the hands of the Allies. To proceed beyond Belgrade and up the Save to the western frontier of Serbia, they would have to control the Frushka Gora mountains and the quadrilateral between the Danube and Save. The British would need monitors, small torpedo boats to deal with the Austrian flotilla, and a mining and antimining force able to make raft and net bridges. Troubridge concluded that if they could not occupy the necessary enemy territory and if the railways were insufficient, it would be preferable to march at least as far as Belgrade on foot rather than attempt the river passage with its known disadvantages and dangers. He also warned that if the British sent an expedition to Serbia, they would have to rely entirely on themselves, for the resources of the country were barely sufficient for the population and Serbian army.21
The Admiralty could hardly have been enthusiastic about the Danube project after Troubridge’s negative report even though Amery had been much more optimistic about the potential of the Serbian railways and the possibility of moving matériel by lighters and tugs up the Danube.22 Nevertheless there still remained the problem of securing control of the Hungarian bank of the Danube so river craft might move unhampered by enemy batteries. The prospect of actually assembling twelve monitors in Serbia where facilities were lacking seemed equally doubtful, quite apart from the diplomatic difficulties of moving the sections through neutral Greece. The dockyard at Belgrade was within easy range of Austrian batteries, and before they could think of assembling monitors there, the Serbians would have had to capture Zemun and the territory beyond it. The promise of monitors soon faded; on 8 July Troubridge received word that owing to Greek troubles, the monitor sections could not be sent by way of Salonika.23 This left only the Danube route open, and that of course was dependent on success at the Dardanelles. There is no doubt that the entire Danube project was linked to the Dardanelles venture and to a certain extent to the political differences within the British government.24
It is hard to avoid the conclusion that the Danube project had great potential for disaster. The British, unless fully supported by the Balkan neutrals, would have been pushing into an area where it was far easier for the Austrians and Germans to concentrate their military forces against them than for the British to reinforce theirs. Troubridge, however, rea
ched a different conclusion when his mission collapsed. He had poured cold water on the Danube proposal in his official report and was consistently critical of the Serbians in his private diary. Nevertheless, when Belgrade fell and Serbia began to go under in October, he wrote: “We are done by reason of striking at the enemy’s foot at the Dardanelles instead of through Serbia at his heart.”25 Unfortunately the logistical, diplomatic, and geographical difficulties of doing this in 1915 were considerable.
The British naval mission was destined never to fulfill any of its grander designs, but there was still the prospect of a form of naval guerrilla war in the waters around Belgrade. Artillery, torpedo tubes, and mines sufficed for defensive measures, although the fluctuating water levels made it difficult to rely on contact mines. The Allies placed much more faith in observation mines, which could remain on the bottom and be fired when an enemy craft was observed to pass over them. The British also were anxious for offensive measures. The means in Serbia were limited, but the Serbians did cover a barge with iron plating as a protection against rifle fire and on 5 January used the barge to cover with rifle and machine-gun fire a flotilla of small boats retaking Little Tsiganlia Island.26 Both Cardale and Troubridge wanted something more potent and requested a picket boat, which could be fitted with torpedo-dropping gear and used against the monitors. The British naval mission finally received their picket boat from Malta on 21 March. It had been shipped by rail from Salonika, and there was considerable difficulty getting it past Greek customs and then through the tunnels and under the low bridges along the railway. There were even more difficulties in launching what the British, somewhat tongue-in-cheek no doubt, dubbed the “Terror of the Danube.” Assuming the Austrians knew of the picket boat’s arrival, Troubridge decided to lull their suspicions and waited a month before using it in a night attack against the monitors in their anchorage above Zemun. The first attempt failed to find the monitors, but on the night of 22 April Lieutenant Commander Kerr managed to reach the Austrian anchorage before he was detected, fire his two torpedoes, and escape unscathed. The British heard two explosions, and ten minutes later a very heavy explosion. They knew the second torpedo had hit the river bank but believed the first had struck the leading monitor. This belief seemed confirmed after daylight when one of the monitors observed the day before was missing.27 The Austrian sources, however, insist strongly that none of the monitors were lost. The Austrians had constructed a dummy monitor with wood and canvas in order to draw the fire of the Serbian and French batteries and thereby cause them to reveal their location. The Serbians, with good intelligence, do not appear to have been fooled, but the dummy monitor may well have been Kerr’s target on the night of the 22d.28
The “Terror of the Danube” never had another chance at an Austrian monitor. The Austrians increased their precautionary measures, and the picket boat, already damaged by shell fire in May, struck a wreck on the night of 25 July and was holed and sunk in midstream. She was quickly raised and repaired, but Troubridge did not find the outlook encouraging. He was confident they could stop any attempt to send munitions to Turkey via the Danube, but the Serbians could not resist a full-scale Austrian and German invasion and intended, if that ever occurred, to evacuate Belgrade immediately. Troubridge realized the evacuation of Belgrade would give the Austrians and Germans “command of the key to the whole Serbian waters of the Danube,” opening it at once for transport of matériel to the Bulgarian frontier. In distant London the Admiralty sadly realized a regular invasion could not be stopped by sending more boats or men. The First Sea Lord curtly rejected the suggestion that Troubridge should be asked if any reinforcements that could be sent to him would be of any use with the words, “No. He would expect his demands to be acceded to and we can’t send him anything.”29
Serbia was doomed once Bulgaria joined the Central Powers in September. A convention was signed at Pless on 6 September by which six Austrian and six German divisions were to be ready for operations on the Serbian frontier within thirty days, whereas Bulgaria would be ready with at least four divisions within thirty-five days. Field Marshal Mackensen was given supreme command of the allied forces. The primary German interest was to open communications with Turkey. The Germans subsequently increased their obligation by another four divisions when it appeared the Austrians could not meet their commitment because of Russian pressure. The basic plan for the opening moves of the campaign was for the main body of General von Kövess’s Third Austro-Hungarian Army, four Austrian divisions reinforced by a German army corps of three divisions, to cross the Danube and Save at Belgrade, while the remainder crossed the Save about 20 miles upstream at Kupinovo. The seven German divisions of General von Gallwitz’s Eleventh Army would cross the Danube downstream from Belgrade at Ram and Semendria with a feint crossing at Orsova. The four divisions of the Bulgarian army would invade from the east with the majority aimed at cutting the Salonika railway at Nish and preventing reinforcements from reaching Serbia via the Vardar Valley.30
The Germans made careful preparations for the river crossings which were such an important feature of the opening stages of the campaign. These resulted in the first appearance by German river craft on the Danube to support military operations. Fourteen motorboats of the Kaiserliches Motorbootkorps were to support the crossings of von Gallwitz’s Eleventh German Army. Technically these were not naval craft, but belonged to the train of the army. The organization was formed by the Prussian Ministry of War to support army operations along lakes, rivers, and the coast. It consisted of a variety of requisitioned small craft, some seaworthy, some purely river vessels, and was initially the “Volunteer Motorboat Corps” with many owners apparently handling their own craft, which were usually armed with a machine gun. The largest, the 24-meter Weichsel, which had formerly belonged to the Imperial Motor Yacht Club of Berlin, was fitted with some plating, a 7.5-cm howitzer, two machine guns, and designated an “armored river gunboat.” There were a few naval officers in command, but the boats themselves generally wore the red-white-black government service flag (Reichsdienst flagge) rather than the naval ensign. The boats supporting the Eleventh Army had been drawn from the Vistula Flotilla and shipped by rail to the Danube. The German motorboats, although the formal titles of their formations would change, stayed on the Danube for the remainder of the war. It is doubtful if any returned to their home ports, and the Weichsel fired some of the last shots of the war on the Danube.31
The operations of the Third Austro-Hungarian Army along the Danube and Save began with a massive bombardment at daylight on 6 October. The Austrian naval forces on the Save (the monitor Szamos and armed steamer Una) supported the passage across the Save by two Austrian divisions, and the Szamos was hit by shell fire and damaged, but able to make temporary repairs herself and continue in action. The majority of the Danube Flotilla, not surprisingly, was devoted to the difficult crossing of the Danube and Save near the Kalimegdan fortress and Grosser Tsiganlia Island. The river crossings began on the 7th. The defenses of the Allied missions were overwhelmed by the scale of the assault. The Serbians had decided to evacuate Belgrade, but there was heavy fighting. The three divisions of the German XXII Reserve Corps crossed the Save by way of Great Tsiganlia Island. They met heavy resistance, and the first attempt to take neighboring Little Tsiganlia Island was repulsed before the Germans succeeded in taking it later in the day. The two divisions of the Austrian VIII Corps that assaulted Belgrade had an even more difficult time. They embarked in pontoons using Grosser Krieg Island as cover by passing around its northern shore before rowing across the final lap to Belgrade. The Austrians had established a bridgehead before daylight, but could not be reinforced during daylight hours, and their proximity to the Serbians and the lack of any means for transmitting spotting information made it impossible for their own artillery to give them proper support. The monitors Bodrog and Maros moved downstream to provide that support, and were soon joined by the Sava, Körös, and Leitha. Austrian and German counterfire occupied t
he Serbian batteries, and the monitors were able to take up a position under the lee of the Kalimegdan to provide close support. Save for the Körös, whose stack was holed, they received little damage at this stage. In the afternoon they were relieved in the role of close support by the monitors Temes (II), Enns, and Inn. The combat was broken off after dark.
The monitors were less fortunate the following day, when poor visibility hampered assistance from Austrian artillery, and once again the monitors were the only source of close artillery support for the Austrian bridgehead. The Maws took a direct hit in the superstructure, and, ablaze, had to haul out of the battle. Shortly afterwards, the Enns and Temes (II) proceeded downstream to join the Körös and Leitha, which were firing from their previous position in the lee of the Kalimegdan. The Enns, when off Grosser Krieg Island, took a direct hit forward below the water line, which flooded the 12-cm magazine. The Enns, ablaze and assisted by the Leitha and Körös, moved out of range and grounded herself on the river bank to bring the leak under control. The Temes (II) turned to engage the batteries in order to draw fire from the wounded Enns, but before her guns came into action received a direct hit in the crew’s quarters aft and was forced to move out of range before running ashore to put out fires and stop the leaks. The flotilla commander then sent the Sava and Inn downstream to take up the fight while the armed steamers Samson and Almos towed the Temes (II) and Enns, respectively, out of the battle. Both later had to spend time in dock in Budapest under repair.