Central Powers Invade Serbia

The First World War was an unprecedented catastrophe that shaped our modern world. Erik Sass is covering the events of the war exactly 100 years after they happened. This is the 204th installment in the series.  

October 6, 1915: Central Powers Invade Serbia 

The First World War resulted from Austria-Hungary’s determination to crush Serbia, but against all expectations the small Slavic kingdom managed to repel a series of invasions with decisive victories over Habsburg forces at Cer Mountain and Kolubara. Subsequently Austro-Hungarian chief of the general staff Conrad von Hotzendorf had his hands full trying to stop the Russian advance in Galicia, and then organizing defenses on yet another front after Italy declared war on Austria-Hungary in May 1915.

But this yearlong respite was only a temporary reprieve, and by the fall of 1915 Serbia’s number was up. The Austro-German breakthrough on the Eastern Front, and the Russian Great Retreat which followed, failed to knock Russia out of the war but did end the Russian threat to Hungary, and so removed the main domestic political obstacle to a new attack against Serbia, as Hungary’s Magyar elite now felt secure enough to support renewed offensive operations. Meanwhile Habsburg forces stabilized the situation on the Italian front with defensive victories at the First and Second Battles of Isonzo, and the Allied attack at Gallipoli convinced Austria-Hungary’s powerful ally Germany of the need to conquer Serbia to open up direct rail communications with the beleaguered Ottoman Empire, in order to send urgently needed supplies and reinforcements to the Turks. 

Last but certainly not least, in July Germany and Austria-Hungary finally persuaded the Bulgarians to join their planned offensive, followed by a military pact detailing Bulgaria’s part in the campaign – effectively sealing Serbia’s fate, as it now faced overwhelming numbers attacking on multiple fronts (any hope of Allied forces coming to Serbia's rescue was dispelled by Greece’s pro-German King Constantine, who refused to allow British and French forces to land at Salonika, effectively repudiating Greece’s pre-war alliance with Serbia; the Allies eventually landed anyway in violation of Greek neutrality – but too late to help Serbia). 

Click to enlarge

The attack would be carried out by Army Group Temesvar under August von Mackensen – battle-hardened troops under a seasoned commander fresh from multiple victories during the conquest of Russian Poland. The German Eleventh Army under General Max von Gallwitz would spearhead the northern assault, supported by the combined Austro-German Third Army under General Hermann Kövess von Kövesshaza, attacking the Serbian Third and First Armies, respectively. From the east the Bulgarian First and Second Armies would attack the Serbian Macedonian, Second, and Timok Armies (the last named for the tributary of the Danube which provided the main line of defense in this region). The Bulgarian First Army was also under Mackensen’s control as part of his army group, while the Bulgarian Third Army stood guard against Romania.

Altogether the Central Powers would field 23 divisions (including ten German, seven Habsburg, and six Bulgarian) numbering around 600,000 men, of which the Austro-Germans contributed roughly 330,000. Against these the Serbian Army – scarcely recovered from the Balkan Wars when hostilities began, and now further depleted by a year of fighting and the ruinous typhus epidemic – could muster ten understrength divisions, numbering around 250,000 men, with another 50,000 from Serbia’s tiny ally Montenegro. The Central Powers also enjoyed a massive superiority in artillery, with Mackensen’s army group employing over 2,000 medium and heavy guns, versus 330 for the Serbs – foreshadowing a repeat of Mackensen’s tried-and-true tactics from the Eastern Front, where Austro-German bombardments simply obliterated the Russian trenches. 

In short, there was never any question about the outcome: Serbia was going to be annihilated. The offensive began on the night of October 5-6, 1915 with a bombardment of the Serbian capital, Belgrade, growing in intensity until large parts of the city were in flames. One observer, the British correspondent Gordon Gordon-Smith, recalled: “The bombardment of Belgrade was one of the fiercest in the history of the present war. Over 50,000 projectiles fell in the town in the first forty-eight hours. Nothing was spared. Over eighty shells struck or fell around the American Hospital… in spite of the fact that a Red Cross flag, visible for miles, was flying from the roof.”

History Place

On October 6-7 the Austro-German troops began crossing the Danube and Sava Rivers, now cleared of mines by artillery shelling, on light river craft (above, German cavalry crossing the Danube) or by fording in places where the rivers or their tributaries were shallow enough (top). Despite the artillery preparation the attackers sustained heavy losses as they proceeded across the wide, slow-flowing rivers and reached shore amidst Serbian machine gun and rifle fire, followed by hand-to-hand combat. Gordon-Smith recalled:

After a number of unsuccessful attempts the German infantry on October 6th managed to get a footing on the right bank of the Danube at Belgrade and three other points. The capital was only defended by a small body of troops, the gendarmerie and a number of Comitadjis or irregulars. The defenders fought their assailants hand to hand. The quays of the Danube were running with blood and piled with German corpses.

The invaders then faced heavy artillery fire in the streets of Belgrade, including British naval guns hurriedly brought up to the capital, which dropped shrapnel shells into the narrow streets with devastating effect. One German soldier, a medical student, bargained with a higher power as his unit advanced into the enemy city under fierce shelling:

When I saw my comrades falling down I thought: Now you are getting your share as well. In the deepest anxiety of my soul I called upon God. “Oh my dear God, please help, help, save me, have mercy with the shot I am getting.” I am prepared to sacrifice an arm or a leg, I also take a shot in the chest… Suddenly I thought about my eyes. If only I’m not blinded. I might be prepared to sacrifice one eye, but rather not even this. If only I’m not blinded.

As expected he was hit, and (understandably) believed the wound was much worse than it actually was:

… I feel a terrible hit against my right ear. It is a feeling as if someone had hit my right cheek with a rubber truncheon. There’s a heavy jerk and then a clear crack of bones. On my left side I see a comrade holding his head with both hands. He has got his share too… There is blood dripping on my hands, too, and my coat. When I see it I scream: I am bleeding to death, I am bleeding to death.

By October 9 the Central Powers were in control of Belgrade, which gave them an important propaganda victory but did little to change the strategic situation. The Serbian government had wisely relocated some months before to a new temporary capital at Nis, and the Serbian Army, seeing the futility of trying to hold the city against overwhelming numbers, also mostly withdrew in the weeks before the Austro-German assault, to mount a more determined defense to the south. Now they were joined by thousands of civilian refugees, who fled the city in long columns, heading into central Serbia on foot or in horse-drawn wagons. T.R.F. Butler, an Irish medical volunteer, described the scene on the road south of Belgrade on the night of October 8-9:

A few minutes later we found ourselves among an immense throng of refugees the whole city, one might say, in retreat moving along the one road that could lead them to safety. The spectacle was the most melancholy that I have ever witnessed. One saw old women struggling along as best they could under heavy burdens and usually there were ill clad, crying children following along behind them. There were wounded soldiers too in groups of three or four, often supporting each other for the order had been given that every wounded man who could walk must do so… When we looked back we could see Belgrade burning in seven different places.

A much more strategically important turn of events was looming in the east: the Bulgarian intervention, which began with attacks by the First and Second Armies on October 12 (followed two days later by the actual declaration of war), appeared to seal Serbia’s fate.  As the Bulgarian guns boomed it became clear that Serbia was doomed, unless by some miracle the French troops now landing at Salonika under General Maurice Sarrail could reach them in time.

The Allies were cutting it close, to say the least: the first French troops arrived in Salonika on October 5, landing cautiously due to fear Greek forces might resist this blatant violation of Greek neutrality (true, pro-Allied Greek Prime Minister Eleutherios Venizelos had invited the Allies to land in Greece, but he was promptly fired by Greece's pro-German King Constantine; in any event by this time concerns about the rights of small neutrals, ostensibly one of the causes of the war, had obviously gone out the window). On October 12 Sarrail himself arrived, and two days later French troops were moving north through the valley of the River Strumiza. But by October 15 the rescue mission had essentially failed, as the Bulgarians captured the key Serbian city of Vranje, severing the rail link between the Allied base in Salonika and the Serbian armies to the north. 

Still the outnumbered Serbs fought on, hoping to at least delay the Central Powers advance long enough to allow wounded soldiers, heavy artillery, and other supplies to be evacuated. Gordon-Smith described the grim determination of Serbian soldiers headed to the front aboard trains leaving the central Serbian town of Kragujevac, at night and in miserable conditions:

Hour after hour we waited in the pouring rain. The streaming platforms were glistening with wet in the crude light of the arc lamps. Train after train emerged from the outer darkness, trundled slowly, axles creaking and groaning beneath the load of men and guns, through the station and were again swallowed up in the obscurity beyond. One had a momentary glimpse of the Serbian soldiers, standing stoically in the open trucks in the pouring rain, or saw the silhouette of the guns, their muzzles pointing skywards, as they passed, the heads of the horses emerging through the openings of the cattle trucks used for their transport.

Ultimately the Serbian army’s valiant resistance made little difference: as in Russia, the Austro-German artillery proved irresistible. A few days later Gordon-Smith witnessed the effect of massed shellfire on Serbian hilltop trenches, and indeed the natural landscape itself:

But nothing could have withstood the tremendous fire of the German heavy guns… Huge shells from the thirty-eight centimetre guns were pounding the crest of the hills, which were smoking like volcanoes as these enormous projectiles burst. So tremendous was their effect that the crests were changing their shape before our eyes. As one gun after another came into action the Serbian position became untenable. They had no artillery with which they could make effective reply to ordnance of this calibre, and we could see the long lines of grey-coated infantry winding down the slope, using woods, ditches, and the ruined villages as cover from the murderous fire of the enemy. A minute or two later a tremendous explosion shook the air, and a couple of miles away a pillar of black smoke mounted slowly into the sky. The Serbs had blown up the last bridge across the Morava.

See the previous installment or all entries.