Battle of Kosturino

The Battle of Kosturino was the first serious clash between British troops and the Bulgarians and the closing act of the Entente’s failed expedition to help Serbia. When the French began to withdraw from the Vardar valley at the beginning of December 1915, the frost-exhausted British 10th (Irish) Division was covering their right flank on the bare ridges near the village of Kosturino, some fifteen kilometres south of Strumica. The Bulgarian Second Army attacked it in thick fog. On 7 December it broke through the front of two Irish battalions, and on 8 December it forced the whole division to retreat. Over the next four days the British and French, pursued by the Bulgarians, withdrew over the Dedeli pass and from around Gevgelija across the Greek border. The battle belonged to the final phase of the Central Powers’ conquest of Serbia.

Name and dates

Kosturino is a village on the slopes of the Belasica range, on the road from Strumica to Dojran. The British official history of the Macedonian campaign speaks of “The Actions of Kosturino” and dates them to 7 and 8 December 1915. The British chronology of the war, on which our timeline is based, likewise records the “Actions of Kosturino (7–8 December)”. The Polish, English and Bulgarian Wikipedias and some studies, however, treat as a single battle the whole engagement from the first Bulgarian attack on 6 December to the withdrawal of the Entente troops across the Greek border on 12 December.

On this page we adopt the dates 6–12 December 1915. The Bulgarian artillery had been shelling the Kosturino ridge since 4 December, but the infantry did not move to the attack until the afternoon of 6 December. The heaviest fighting took place on 7 and 8 December, and over the following days the Bulgarians pursued the retreating British and French all the way to the border. According to the British official history, the last British units crossed into Greece in the early hours of 12 December and the French late in the evening of the same day. The Austrian official history also states that the last Entente troops entered Greek territory on 12 December.

Background

The British 10th Division had come to Salonika from Gallipoli at the beginning of October, together with the first French troops. For a long time it was not allowed to cross the Serbian border, and its commander, Lieutenant-General Bryan Mahon, soon took command of all British troops at Salonika. In Serbia the division was temporarily commanded by Brigadier-General L.L. Nicol. On the night of 20/21 November its 30th and 31st Brigades relieved General Maurice Bailloud’s French 156th Division on the sector from Kosturino to Lake Dojran. The French were at that time holding out on the Vardar and the Crna at Krivolak, and the British were to cover their right flank and the railway from Salonika.

The terrain was wild and almost roadless: steep ridges, rocks and stunted oaks. The British took over from the French badly sited positions, overlooked from the higher hills held by the Bulgarians. Trenches were hard to dig in the rocky ground. On 26 November rain began to fall, turning into a blizzard, and then came a hard frost. The soldiers, soaked to the skin, had no winter equipment, and some of them even lacked greatcoats. According to the British official history, 23 officers and 1,663 men of the division had to be evacuated to Salonika because of frostbite, exhaustion and general debility. Many of the rest had not recovered from Gallipoli, and in some battalions almost half the strength consisted of newly arrived men from various regiments.

After the Serbian defeat on the Field of Kosovo, General Maurice Sarrail, commander of the French Army of the Orient, decided to fall back to Salonika. On 3 December the French began their withdrawal from the loop of the Vardar and the Crna. The Bulgarians, freed from their fears about Greece and from the fighting with the Serbs, had meanwhile brought considerable reinforcements to the Macedonian front. According to the British official history they now had about 80 battalions there, including three brigades of General Dimitar Geshov’s 2nd (Thracian) Division between Gradec on the Vardar and the village of Ormanli on the slopes of the Belasica. The whole Second Army was commanded by General Georgi Todorov. The withdrawal of the French from the sector next to the British, and of the 10th Division itself, was not planned until 14 December.

Course of the battle

Rocky Peak, 6 December. On 4 and 5 December the Bulgarian artillery shelled the Kosturino ridge. Thick fog had hung over the mountains since 2 December. At 2.30 p.m. on 6 December the fire intensified, especially on the sector of the Connaught Rangers battalion and on the advanced post the British called Rocky Peak. This was a bare, rocky knoll some 800 metres in front of the main line, from which the positions of the 30th Brigade could be enfiladed. It was held by only one company of the Royal Irish Fusiliers. In the afternoon the Bulgarians broke into it but were driven out with the bayonet. Mahon came to Nicol’s headquarters and ordered another brigade to be held ready at Salonika for transport by rail.

The breakthrough, 7 December. Before dawn on 7 December, in thick fog, the Bulgarians crept up the gullies below Rocky Peak and took it with the bayonet. Until the last moment the defenders could not tell friend from foe in similar uniforms. According to the British war correspondent George Ward Price, who was then with the army in Macedonia, about 30 Irishmen were taken prisoner. The Bulgarians hauled machine guns and a mountain battery up to the summit and began to enfilade the line of the 30th Brigade. Between 9 and 10 a.m. an attack on the Connaught Rangers was repulsed, and the French on the left flank beat off an attack on their sector. At about 2 p.m., under fire from the flank and the front, the companies of the Hampshire battalion fell back. At about 2.30 p.m. the Bulgarians, regardless of losses, attacked the Connaught Rangers in dense masses and broke their line after hand-to-hand fighting. According to the British official history, citing a Bulgarian source, the main attack was carried out by two infantry regiments, the 14th and the 28th. Ward Price estimated that at the point of the main attack the Bulgarians had a fourfold superiority. The Connaught Rangers battalion, which had gone into the line 960 strong, had in his account only 350 men left by evening.

The Bulgarians did not pursue the Irish vigorously, but in the confusion the crew of one battery near Kajali concluded that the whole front had collapsed and abandoned their guns, taking away the breech-blocks and sights. For the same reason a second battery near the village of Prsten was abandoned. The guns had earlier been hauled up the steep slopes on ropes and would in any case have been hard to save. In the evening the 30th Brigade occupied a second line of defence on a hill the British called Crête Simonet, and the 31st Brigade withdrew to the hills north of the village of Tatarli. Mahon telegraphed to Salonika for another brigade. The first battalion of the British 22nd Division reached Dojran that same night, and General Bailloud sent two battalions and a mountain battery.

Crête Simonet, 8 December. In the morning two companies of the Royal Dublin Fusiliers occupied the forward hill of Crête Rivet. At about 2 p.m. the Bulgarians broke into it in great numbers, and the Irish fought their way back, losing 64 men. At 3.30 p.m. General Nicol learned that the Bulgarians had also massed in front of the 31st Brigade and were coming down a gully near the village of Memeshli to turn the division’s right flank. The brigade commander, convinced that he was in danger of being surrounded, ordered a retreat, and at 5 p.m. Nicol ordered the 30th Brigade to withdraw as well. As the rearguard was going down the slope in the darkness, the Bulgarians rushed onto Crête Simonet with shouts, to the sound of bugles and the glare of flares, but went no further. During the night the division occupied a new line from Lake Dojran along the Kara Bail ridge to the Dedeli pass on the road to Dojran.

Retreat to Greece, 9–12 December. On the night of 8/9 December the French withdrew from the neighbouring sector. Their transport climbed the road to the Dedeli pass in full view of the enemy, but until noon it was hidden by fog. Sappers blew up the culverts on the road behind them. On 9 and 10 December the Bulgarians did not attack the British. On 10 December Mahon handed over command of all British troops in Serbia to Major-General Gordon, commander of the 22nd Division. To the west of them the French were withdrawing down the Vardar, fighting heavy rearguard actions at Demir Kapija and clearing supplies from the station at Gevgelija. Sarrail did not want to hurry until they had been removed. On the evening of 10 December General Bailloud, alarmed by Bulgarian detachments infiltrating through the gullies in the fog, pulled his troops back further than planned and ordered the British to withdraw south of the lake, except for one brigade. At 1 p.m. on 11 December a column of the Bulgarian 11th (Macedonian) Division occupied the village of Bogdanci, cut the French telephone lines and captured ammunition wagons. The French fell back towards Dojran, often without warning the British. One company of the 9th Battalion, King’s Own, which did not receive the order to retreat in time, ran into a Bulgarian battalion resting by the road during the night and was destroyed in a bayonet fight. Of about 140 men only 17 got across the border. The rest of the brigades crossed into Greece along a road crowded with French transport, refugees and herds of cattle. In the early hours of 12 December all British troops were across the border, and the French crossed it late in the evening.

The Bulgarians halted at the border. The commanders of the Central Powers had decided to drive Sarrail out of Serbia, but the Chief of the German General Staff, Erich von Falkenhayn, not wanting to push Greece into the arms of the Entente, forbade crossing the Greek border “in any case, not even with aircraft”. According to the British official history, on 12 December French headquarters learned from a secret Bulgarian source that the Bulgarians would halt two kilometres short of the border, except in the area of Dojran. Ward Price reported that the Bulgarian advance guard stopped at the Greek frontier post on the edge of Dojran, and that the staff of the 30th Brigade had left the town only ten minutes before it arrived.

Losses

According to the British official history, the British lost in the whole expedition to Serbia, the vast majority in the December fighting, 33 officers and 1,176 men: 99 killed, 386 wounded and 724 missing. Almost all the losses were borne by the 10th Division, and more than half of them by the two battalions that took the main blow on 7 December: the Connaught Rangers and the Hampshires. The British abandoned eight field guns. Some studies state that the French lost about 1,800 men in this fighting and the retreat. Bulgarian losses are not known. A Spanish officer who observed the campaign on the Bulgarian side, and whom the British official history cites, stated only that in one attack on the French on 9 December a single regiment lost 400 killed, and that in the whole pursuit the Bulgarians took 1,234 prisoners, 14 guns, eight of them British, and 62 artillery wagons. Both the British and the Bulgarians agreed that the attackers’ losses had been considerably greater than the defenders’.

Significance

At Kosturino the Bulgarians, better prepared for mountain warfare and with plentiful mountain artillery, inflicted a painful defeat on the British. They did not, however, manage to cut off or destroy Sarrail’s forces. The British official history, though critical of the French commander, judged that the retreat had been efficiently directed and very well carried out, and that the fog which had helped the Bulgarians in their attacks had also screened the withdrawing columns. Almost all the equipment was got away. The most serious exceptions were the breakthroughs on the front of the 10th Division on 7 December and of the French on 11 December.

The battle closed an expedition that was meant to save Serbia and ended with a return to Greece. The Entente troops withdrew to Salonika and began to fortify an entrenched camp around the city. The Bulgarians, halted at the border by the Germans, dug in on the hills north of Lake Dojran. For the next three years the line of the Salonika front ran through the same mountains in which the 10th Division had fought in December 1915.