Serbia in World War One

The foreign policy position of Serbia was extremely challenging not only because it had a superior enemy at its borders, but also due to the constant pressure by allies who were trying to attract the neutral Italy and Bulgaria to their side. That is why Serbia was under a strong pressure to give up a part of its territory to its eastern neighbour and not to dispute Italy the right to a part of the Adriatic cost. In order to win Italy over, the Allies made a secret London Pact on 26 April 1915, promising Italy the South Tyrol, the Julian district with Trieste, Gorizia and Postojna, and Istria, the Kvarner islands, northern Dalmatia including Zadar and Šibenik and a number of islands. Since Serbia in its war program emphasised its aspiration for the unification of all South Slavs, it did not succumb to these pressures even at the cost of tense relations with its Allies. When offered by the Allies to make a deal with Italy regarding demarcation of borders, Serbia responded that it is not ready to „trade“ with its own people, specifically Croats and Slovenes. Serbia also was never given the status of an ally of the Entente powers, which had negative consequences on warfare. Due to the defeat of the Allies at the fronts in 1915, the pressures on Serbia became even stronger.
Achieving success at other fronts, the Central Powers in September 1915 started to concentrate troops in order to launch the final battle against Serbia. This would mean for them establishing a link with Turkey and making further progress towards the Middle East. Preparing for the offensive, on 6 September 2015 in Pleso they forged a secret agreement with Bulgaria to take part in attacking Serbia defining at the same its occupation zone. They had joint forces of about 800,000 soldiers of the Central Allies, under field marshal August von Mackensen, one of the most competent German officers, after whom this army was named. Serbia was defended by 300,000 soldiers distributed along the front of about one thousand kilometres.
After ferocious infantry preparations, the attack of superior Austria-Hungarian and German forces began on 7 October 2015 from the north, across the river Sava and the Danube, and from the west, across the river Drina. The power of the attack was especially hard on the capital of Belgrade, which suffered huge destruction. Apart from French infantry soldiers and Russian sailors, the defence of the city was aided also by civilians, among them Jews from Dorćol. The heroic defence of Belgrade and the words of major Dragutin Gavrilović about fighting to the last man standing, have been preserved in the collective memory of the Serbian people. Battalion commander, major Avram Beraha, was among the prominent officers in the defence operation, who commanded the troops during the defence. Despite the heroism, the defence was broken after two days, the city was occupied, and the field marshal Mackensen paid tribute to the defenders. The Mackensen army made slow progress because of the tireless defence of the Serbian Army, so back-up was needed from other fronts. The Bulgarian Army attacked Serbia on 14 October 1915 and a month later managed to take Niš, Skopje and Kačanička gorge, whereby it cut off the road to the Serbian Army on their way towards the allied forces in Greece.
The Serbian Army was withdrawing before the battle, avoiding siege, but the situation was becoming increasingly dire. Allies sent two divisions from Greece to help Serbia, but this was both insufficient and untimely. Despite the almost desperate situation, the Government and Prince Regent Aleksandar were committed to continue the struggle by rejecting the capitulation offered by the enemy. Attempted break-through towards Skopje and Greece failed and on 25 November 1915 a decision was made to retreat towards the Adriatic across Kosovo and Metohija, Montenegro and northern Albania. The Serbian Army believed that capitulation would be the worst solution as that would mean losing both the state and the Allies, and that the only solution was the retreat of the army and state institutions towards the Adriatic and connecting with the Allies. Nikola Pašić sent a message to soldiers that „the state will continue and preserve itself; it will, thus, exist, although on foreign ground, as long as the government and the army is there, irrespective of its strength“.
By the end of November 1915 Austria-Hungarian forces launched an offensive on Montenegro. The tireless defence by Montenegrin Sandžak army facilitated the safe passage of the Serbian Army and refugees. In the decisive battle near Mojkovac on 6 and 7 January 1916 the Montenegrin army under the command of General Janko Vukotić won a brilliant victory. However, the Montenegrin defence along the western line suffered a complete breakdown. The Montenegrin HQ on 11 January 1916 asked for a truce, while Austria-Hungarian forces continued its break-through, occupied the capital Cetinje and put a siege on the Montenegrin army near Podgorica. King Nikola left the country and crossed to Italy, and on 25 January 1916 in Cetinje the capitulation of the Montenegrin army was signed. Soon afterwards military administration was established in Montenegro.
Having destroyed its heavy weapons, the Serbian Army at the end of November 1915 started its troublesome retreat towards the Adriatic, organised in three directions: towards Shkodra, Lesha and Elbasan. King Petar, the Prince Regent Aleksandar, the Government, the national deputies, members of the diplomatic corps, distinguished intellectuals, and a huge number of refugees including many children were retreating along with the Army. While advancing through Albanian snow-covered mountains, without food or shelter, exposed to attacks by Albanian tribes, a great number of Serbian soldiers and civilians lost their lives on daily basis. According to the memory of the French envoy to Serbia August Bopp, who arrived to Shkodra with the Serbian Army, the soldiers „looked completely exhausted, like living skeletons […] only here and there they would utter the word bread, that was the only word they could gather the strength to utter“. The majority of the Serbian Army with refugees arrived to the area between Shkodra and Durres at the beginning of January 1916. However, their evacuation to Greek islands of Corfu and Vido started only at the end of the month due to obstructions of the Italian and British Government. After a strong intervention by the Russian Tsar Nikolai II, the evacuation was accelerated and Italian ships were joined by French and British ones. About 140,000 soldiers were evacuated to Corfu, another 110,000 were evacuated to the French Colony Tunisia to Bizerte, while 2,000 patients were transferred to hospitals in France. A great number of refugees were evacuated to allied and neutral countries. Total losses of the Serbian Army in combat and during the retreat during 1915 are estimated at 250,000 people, while another 140,000 civilians died or went missing.
The evacuation did not represent the end to the mass dying of the exhausted Serbian soldiers and refugees. About 5,400 people died at the islands of Corfu and Vido and about 1,000 in Bizerte. Soon after arrival the accommodation and food conditions improved and the Serbian Army was recuperated and reorganised rather quickly. The Serbian Government sent pupils and students, a total of about 5,500 to schools, mostly in France and to a lesser degree to Great Britain and Switzerland. At Corfu the Government of Nikola Pašić again became operative, and Nikola Pašić served also as Minister of Foreign Affairs. After the national deputies got together the National Assembly resumed its work and this meant the continuation of work of diplomatic offices and resumed printing of Serbian press. With the material assistance provided by the French and partially British armies, the Serbian Army was reorganised into three armies. In mid April 1916 the transport of the Serbian Army to the Allied fronts to northern Greece began.
While the Army was retreating through Albania, Serbia was occupied, and the occupier did so with the ambition to prevent it from ever becoming an independent state again. The ambitions of the Bulgarian occupier went even further. At the time of attack on Serbia in October 1915, Austria-Hungary and Germany had somewhat different plans regarding the future of the occupied Serbian territory. There were also differences concerning the future of the second Serbian state, Montenegro. In Austria-Hungary there were differences between the Austrian and the Hungarian parts of the Monarchy. Yet, all participants in the aggression shared a position that Serbia as a state should be destroyed. Such a position started to be operationalised at end of November and beginning of December 1915, when the majority of Serbia was occupied and when it seemed that its army was experiencing a complete collapse. The key actors in Vienna advocated an annexation of a big part of Serbia and Montenegro, while the remaining parts would be under military administration, in accordance with the agreements with the German and Bulgarian governments. The Hungarian Prime Minister Istvan Tisza advocated annexation of territories along the Sava river, to which Hungarians and Germans were to be colonised. In order to disturb the Serbian ethnic continuity they were to be colonised in greater numbers in the regions of Srem, Bačka, and Banat. The plans were also to reduce Montenegro in size and disconnect it from the sea. The remaining parts of Serbia and Montenegro were to be a protectorate, politically and economically dependent on the Monarchy. Bulgaria was trying to get an even greater part of Serbia than promised under agreements with the Central Powers. Germany supported Bulgarian aspirations, and itself did not have territorial aspirations towards Serbia. Germany, too, supported the destruction of the Serbian state attempting to have its territory as a part of its „great economic area“.
The conflict regarding the occupied Serbian territory lasted until 1 April 1916 when, under Germany-led arbitration, the demarcation line was finally drawn between the Austria-Hungary and Bulgarian occupation zone. On 1 January 1916 a Military General Government was established in the Austria-Hungarian occupied territory which, after the final demarcation, covered the districts of Šabac, Belgrade, Valjevo, Smederevo, Kragujevac, Gornji Milanovac, a part of the Čuprija district, as well as districts of Užice, Čačak, Kruševac, Kosovska Mitrovica, Novi Pazar and Prijepolje. The Bulgarian occupation area covered the eastern, southern and central Serbia, parts of Kosovo and Metohija, and Macedonia. It was divided into two administrative regions: the Military-Inspection Area of Morava, with its seat in Niš, and the Military-Inspection Area of Macedonia, with the seat in Skopje. The Military-Inspection Area of Morava consisted of six districts: Požarevac, Negotin, Zaječar, Ćuprija, Niš, and Vranje (which included also the Pirot district).
The Austria-Hungarian administration was characterised by ruthless exploitation of natural resources, mass detention of the population in detention camps, and destruction of the political and national awareness among Serbs. The occupying administration, in its propaganda, was portrayed as „civilising“. The destruction of Serbian national culture was carried out by different means, primarily looting, but also through schools and other means. Along with other national features, the Cyrillic script was prohibited, the “Croatian script” (the Latin alphabet) was introduced in schools, Serbian textbooks were prohibited, strong censorship was introduced, prohibition covered the books by Jovan Jovanović Zmaj, Branko Radičević, and a number of other writers. German and Hungarian languages became mandatory school classes. Significant Serbian Medieval monasteries were plundered, bells were removed from churches, museums, archives and libraries were systematically plundered. The Serbian Orthodox Church was also a target, as a key actor in preserving the national identity. Some 200 priests were detained, the Metropolitan Archbishop and a part of the clergy were in refuge, so the regular church activity was paralysed. The Austria-Hungarian occupation administration tried to transform Serbs into obedient and loyal Monarchy subjects, shaping their national awareness and culture to their desired model.
The economic policy of the Austria-Hungarian occupier brought the country to misery and hunger. Industrial companies, banks and trading companies were transferred by decrees to the authorities of the military administration and state monopoly was introduced over a number of vital products. There were continued requisitions, and the market was completely opened to goods from Austria-Hungary. Food was rationed, and the daily rations were repeatedly reduced. This led to mass starvation of the population and starvation to death. Only in September 1917 more than 8,000 people died of starvation. This most severely affected the most vulnerable, the children and the poor, predominantly in urban areas.
The General Military Government, however, did not question the existence of the Serbian nation. The situation was quite different in the Bulgarian occupation zone. Bulgaria was sticking to the principle that the total Slavic population of Macedonia and the Morava region (areas within the watershed of Južna Morava, Velika Morava and party Zapadna Morava) is in fact Bulgarian, while the Serbian national sentiment is a result of violence exercised by the Serbian state. This was the basis for total Bulgarisation of the nation, which started right after establishing the occupying authority and lasted throughout the war until liberation. Together with the military, the police and the administration, Bulgarian teachers arrived to the occupied areas. Although the occupied territory also had other nations like Albanians, Turks, Greeks, and Jews, the Bulgarisation was aimed primarily at Serbs. As stated by the Austria-Hungary liaison officer, Bulgarisation was characterised by two major trends: „destruction of the upper class (inteligencia) of the local population, and the introduction of the Bulgarian language“. Deportation and detention of teachers, priests, officers, and others started right away, and many of them were atrociously murdered. The Serbian language and books were prohibited, Serbian personal names were Bulgarised, all family patron saints and other holidays were prohibited, along with the Serbian national costume, especially the “šajkača” cap. A system of ruthless economic exploitation was introduced, which led to hunger.
Already during the attack on Serbia in October 1915 the Bulgarian troops performed great atrocities over the Serb prisoners of war, the wounded and the civilians. After hearing of the manner in which the Bulgarian army acted and the situation in the Bulgarian occupation area, the Serbian Government was convinced that this represents the destruction not only of the Serbian national awareness, but also physical destruction of a great part of the nation, primarily the elite. That is why the government moved on to systematically gather data regarding the crimes committed by the Central Powers, and it turned out that the most numerous and most atrocious were the Bulgarian crimes. To boost this effort of gathering data, the Serbian Government again engaged professor Reiss. At the invitation of the Prime-Minister Pašić, he arrived to the Serbian Army Headquarters in mid October 1916. Already in April 1917 the Serbian Ministry of Defence in Thessalonica published a brochure by Reiss titled The Destruction of the town of Bitola. Along with other violations of the international warfare law, this brochure stated that the Bulgarian-German artillery bombed the liberated town of Bitola by poisonous gas granates. In just one bombing campaign, during the night of 16/17 March 1917, such poisonous gas bombing killed 61 persons, among them 25 women and 32 children. During the first bombing of Bitola, the granates targeted the Turkish and the Jewish quarters and buildings in the vicinity of the Serbian Archbishop’s Home, in whose cellar 37 refugees were murdered by gas.
Until summer of 1918, it was impossible for the Serbian Government, and even the Serbian Red Cross, to communicate with the occupied regions. Nevertheless, information regarding the situation in the country arrived through various channels. A key actor in this was the neutral Holland, which represented Serbian interests in Bulgaria. Based on the information which he received through various means, Pašić sent a number of protest notes on behalf of the Serbian Government in the period from 20 September 1916 to 15 April 1918, addressing them to governments of allied and neutral countries, signatories of the Hague Conventions, regarding the Bulgarian violations of international warfare law. A big issue for the Serbian Government was the issue of sending assistance to the country, primarily for the detained. Identifying the actual number of Serbian prisoners of war, and especially civilian detainees, proved to be a great problem due to the stance of Bulgaria regarding the status of the occupied territory and the population therein.
Under the pressure of the international public, the Bulgarian Red Cross at the end of 1917 provided the information that in Bulgaria there is only 21,000 Serbian prisoners of war, while civilian detainees were not even mentioned. This was far from the actual number, because it was known that only from the Morava Military-Inspection Area the Bulgarian detention camps in 1917 housed between 60,000 -65,000 persons. Among them, there were about 8,000 women and girls who were sold, for golden money, by Bulgarians to Turks. Professor Reiss determined that these were mostly girls aged ten to fifteen. A big group of Serbian prisoners of war was sent to Turks to Asia Minor, and they were dying in great numbers while working to finalise the Bagdad railways and communications for the Turkish Army. After Bulgarian capitulations, about 52,000 detained persons returned to Serbia, although the Bulgarian Red Cross reported slightly earlier that the number of detained civilians was 14,324.
The next great wave of violence against the Serbian population started during the Toplica uprising, which broke out at end of February 1917. The actual scope of mass destruction of the Serbian population and material destruction became clear only after the liberation. The National Assembly of the Kingdom of Serbs, Croats and Slovenes established an Inquiry Committee to investigate the causes of the uprising in the districts of Toplica, Vranje, Niš, and some others. In March 1920 the Committee submitted its comprehensive report on the persecution during the Toplica Uprising stating that the number of victims was 35,000. Within preparations for the Paris Peace Conference, a special Inter-Allies Commission was established in 1919 to investigate crimes committed by the Bulgarian occupier in Serbia. According to the reports of this Commission, during the Toplica Uprising in the spring of 1917 a total of 20,000 Serbs were killed, of all ages and both genders. Most were killed by Bulgarians, predominantly by cold weapons, while others were killed by the Austria-Hungarian army and gendarmerie. The killing was accompanied by enormous destruction, plundering and violence.
The World War One was unique also in terms of massive detention of civilians in concentration camps. Detention was used not only against the population of the occupied countries, but also the „unloyal“ individual compatriots. Detention strongly affected the Serbian population, both in Serbia and Montenegro, and in Austria-Hungary. In Serbia proper, both during military operations, and after the establishment of occupation administration in the autumn of 1915, civilians were massively detained along with prisoners of war. According to incomplete data, during the Great War there were about 50 bigger and smaller concentration camps (transit-temporary and permanent) in AustriaHungary detaining several hundreds of thousands of civilians, citizens of the Monarchy and citizens of occupied countries. In the territory of Yugoslav countries the Monarchy ran about 20 concentration camps, mostly in Slavonia, Srem, and Croatia (Koprivnica, Virovitica, Osijek, Čepin, Tenja, Borovo, Varaždin, Dalj, Petrovaradin, Donji Miholjac, Pleternica, Pačetin, Bobota, Belišće, Bršadin, Turanj, Poganovci, Žegar), the largest one being in Doboj, Bosnia.
Right after the ultimatum to Serbia, Austria-Hungary started mass arrests and detention, using already prepared name lists, and declaring the detainees to be hostages. These were not just members of the Serbian elite, but also all the others, among them a great number of women and children. The Serbian population of Bosnia and Herzegovina was targeted with special force, especially in eastern parts, as well as the regions of Srem and Banat. The pretext used was the operations of the Serbian and Montenegrin armies in eastern Bosnia and in Srem in the autumn of 1941. Just in Srem 320 people were killed, and the total number of people detained from 41 villages until the end of 1914 was close to 30,000. Another form of terror was expulsion of Serbs from Srem and their settlement in the villages of western Slavonia, which suffered a great economic burden due to this. In the region of Požega district there were about 13,000 such expelled people, of which about 1,000 Serbs were detained in the concentration camp in Pleternica, while the Serb villages housed 12,000 such expelled people (women, children and elderly) from Srem. From the town of Zemun about 6,000 Serbs were detained in camps in Dalj and Borovo and expelled to western Slavonia.
Of the concentration camps in the territory of Yugoslav states within the Monarchy the biggest camp was in Doboj. The first prisoners were brought to this camp in December 1915. A total of 45,791 people were detained in this camp, of which 33,669 were civilians from Bosnia and Herzegovina (among them more than a half were women and girls), another 9,172 were from Serbia and 2,950 were prisoners of war, men and women and children from Montenegro. By 1 May 1917 the number of people who died in the camp was 1,901 officially, but the number was certainly much higher. According to death records only during April of 1916 643 children died. The Doboj and other camps across the Yugoslav states within the Monarchy were also used as transit camps from which detainees were transferred to other camps in Hungary and Austria.
Already during the first weeks of war against Serbia, camps were established in Austria-Hungary for prisoners of war and the civilian populations from Serbia and for Serbs from the Monarchy. Among the first were the camps Neszider (another name: Sopronnyek), Czegled, and Arad. At the beginning of the war about 1,500 people from Šabac were detained in Czegled and Arad (some sources state as many as 2,000) of which over 200 women and girls. From September 1914 hundreds of civilians from western Serbia were detained in the camp in Tuzla. After taking Belgrade at the beginning of December of 1914 more than 1,500 people were deported from the capital, among them about 150 women and girls.
Mass detentions of the Serbian and Montenegrin population continued also after their breakdown and after the establishment of the occupation administration. Apart from the above camps, they were also detained in camps Nagymegyer, Boldogasszony, Aschach, Mauthausen, as well as in the largest camps: Heinrichsgrün and Braunau am Inn. Before deportation from Serbia, a great part of prisoners were first detained in the Kalemegdan camp in Belgrade. Several thousand people went through this camp just during 1918, and on daily basis it housed up to 500 detainees. According to professor Reiss, the biggest camp for Russian, Serbian and Montenegrin prisoners of war was in Heinrichsgrün where, at the beginning of October 1916, there were 66,000 detainees. Among these, there were about 12,000 Serbian civilians, mostly from the region Pomoravlje. Apart from camps for prisoners of war and detainees, there was a special camp for Serbian children over five years of age. Detainees from this camp were subsequently transferred to the camp in Braunau am Inn where, in February 1918 more than 3,200 Serbian civilians died, including a significant number of children.
The camp in Braunau am Inn had a Serbian Children Detention School established. This was, in fact, a children’s camp in which the children were „re-educated“ and stripped of their national identity. Serbian history was prohibited and mention was made only of events in which Serbs were humiliated. The language of instruction was Croatian, and starting from second grade it was the German language. Disobedient Serbian teachers were transferred to forced labour from which very few returned.
The camp in the Arad fort was one of the worst and one with highest mortality rates. Of about 15,000 detained Serb civilians from Serbia and from Austria-Hungary and Serb soldiers, many of whom came there wounded, about 4,317 died in this camp of disease, starvation, and abuse. Camp detainees were obliged to perform physical labour. The destiny of small children was especially tragic, and a report from the Arad camp states that there were more than 400 children there. A few months later only 30 to 40 were still living, all of them very exhausted and almost dying.
According to the official study of the Serbian Government, as of 1 February 1918 the total number of Serbian prisoners of war in Austria-Hungary was 93,473 and the number of detained civilians was 60,000. That number according to Austria-Hungarian sources was greater, specifically almost 64,000 detainees. The biggest number of detainees (36.621) was in Braunau am Inn, to which detainees from Heinrichsgrün were transferred, the next in terms of numbers was Nagymegyer with 11,876 and Aschach with 4.418, and Boldogasszony with 2,910. In the territory of Hungary the detainees were in numerous smaller camps, the biggest among them being Czegled with 1,231 detainees. According to the date of the occupation administration in Serbia, at the end of 1917, the number of detainees from Serbia had risen to 77,000. The document that the Government of the Kingdom of Serbs, Croats and Slovenes presented at the Peace Conference in Paris at the beginning of 1919 states that there was a total of 182,000 Serbian detainees, of which in Bulgaria 120,000; in Austria-Hungary 60,000; and in Germany 2,000. According to the calculations by professor Reiss, about 150,000 civilians were deported and detained only to camps in Austria-Hungary, of which 80,000 lost their lives, which is 44%.
Despite mass crimes and repression, occupation authorities were aware that their success was limited. As the war moved on and as news of Allies’ successes and victories of the Serbian Army came in, the spirit of resistance was getting stronger. Already in March 1916 an Austria-Hungarian source states that it is wrong to think that the Serbs feel defeated. A year later the same source estimates that „among the majority of the population there still is fanatical hope of Serbia’s independence“. Such sentiment, coupled with the despair due to the very harsh occupation, were expressed through sporadic armed resistance of the population which, near the end of February 1917 in Toplica, grew into a general armed uprising. That was the only major national uprising during World War One. The rebelling army soon liberated Kuršumlija, Prokuplje, and Lebane, and at the beginning of March 1917 it came very close to Niš.
This uprising was not linked to the Serbian Army HQ in Thessalonica, and was an expression of rejecting the occupation, which made Serbs feel disfranchised, humiliated and exploited. As the uprising was a threat to both the Bulgarian and the Austria-Hungarian occupation administrations, their joint forces on 8 March 1917 undertook a general campaign attacking the rebels, using over 60,000 Austria-Hungarian and Bulgarian soldiers, and the combat was joined by the Bulgarian and German aviation. The rebels’ forces were broken by 25 March 1917, and some smaller groups moved on to waging guerrilla resistance. Operations against the rebels were accompanied by mass crimes against the civilians and destruction of whole villages. Although most of the crimes were committed by Bulgarian units, atrocities were just as fierce on the side of the Austria-Hungarian forces. Sporadic resistance of the “comits” (chetniks) did not stop throughout 1917 despite the death of their commander Kosta Vojinović, one of the leaders of the uprising. From beginning of 1918 guerrilla actions increased in number on both Austria-Hungary and Bulgarian occupation areas. During the progress of allied and Serbian units in September and October 1918 there was a whole series of spontaneous uprisings in Serbia and Montenegro, which significantly contributed to the liberation of the country.
After the final decision by the Allies that the Balkan Front is significant and that it needs to be maintained and strengthened, the dilemmas regarding the engagement of the Serbian Army were resolved. The Serbian HQ requested that the Army remains one and under its command, which had a military and even more a political significance. In contrast to this, France requested that Serbian units be subordinated to it. This led to a long dispute, but the Serbian view prevailed. By June 1916 about 127,000 Serbian soldiers were transferred to the Allied front in northern Greece and by the end of the following month this number grew to 152,000. At beginning of August 1916 there were at the Thessaloniki front 127,800 French and 119,000 British troops.
The Serbian Army was located at the central part of the allied forces front north of Thessaloniki and therefore in the Serbian collective memory the Balkans Front is preserved as the Thessaloniki front. Allied forces in Greece were under the command of French commanders, they consisted mostly of French and British troops, along with some significant Russian and Italian units. It soon proved that the most active part of the front with the greatest striking power was the part with the Serbian Army. The coming of the Serbian Army to the Allied Forces front in Greece was a great surprise both for the Allies and for the enemy. In contrast to the belief that Serbia along with its Army was destroyed, it turned out that it still exists as a major military and political actor that has to be reckoned with.
In summer 1916 the Allies managed to win over Romania to join the war on their side, and a plan was drawn up for joint actions in which the Serbian Army was to play an important role. The offensive at the Thessaloniki Front was to begin on 20 August, and Romania was to attach Austria-Hungary on 27 August. Central powers noticed that an offensive was being prepared, so the Bulgarian Army started a powerful offensive on 17 August. They stroked the heaviest blow in the sector under the control of the Serbian Third Army. Allied forces were made to retreat, but the situation was soon stabilised. Commander Živojin Mišić was urgently summoned from Corfu to take command over the First Army. Command over the Third Army was taken over by General Miloš Vasić. The counter-attack by allied forces started on 14 September 1916 and the main actor was the Serbian First Army. In a three day bloody combat at Gorničevo the Bulgarian forces were broken and made to retreat. Fierce combat continued on mountain Nidže for the mountain tops of Kajmakčalan, which after severe losses was finally won on 30 September. Thus, the Serbian Army was back on its state territory. After the deep advance of the First Army and the battle of Crna Reka, Bulgarian forces retreated 40 kilometres so that the Russian and Serbian forces entered Bitola on 19 November 1916. North of Bitola, Bulgarians and Germans stopped the advance of the Allies and this meant moving on to trench war. This front line remained intact for almost two years until the decisive Allied forces offensive. The Serbian Army confirmed its value, but paid a very high price because 28,000 soldiers were killed. Bulgarians and Germans suffered much greater losses, specifically 68,000 soldiers killed and about 7,700 prisoners of war. Due to heavy losses, the Serbian Army was reorganised again and since that time had only two armies. The First Army, under commander Živojin Mišić, consisted of the Moravska, Drinska and Dunavska divisions, while the Second Army, under commander Stepa Stepanović, consisted of Šumadijska, Timočka and Vardarska divisions. Other allied armies suffered much lower losses, which goes to say that the Serbian Army took the heaviest burden of combat.
Among the ranks of the Serbian Army there were also volunteers from Boka, Hercegovina, Montenegro, as well as soldiers who deserted the Austria-Hungary Army. Due to heavy losses during the retreating from Serbia and in combat on the Thessaloniki front, it became very important for the Serbian Army to attract as many volunteers as possible. The volunteer movement was also encouraged by the Yugoslav Committee for political reasons as Yugoslavs from Austria-Hungary fighting on the side of Entente would strengthen their role as actors of unification. They counted on Yugoslav immigrants in the USA and in British dominions, Canada, Australia and New Zealand, and especially on tens of thousands Yugoslavs who, as Austria-Hungarian soldiers, were prisoners of war or surrendered to Russians and Italians. In December 1916 a Serbian Embassy in Washington was established with a special task to recruit volunteers. Lieutenant colonel Milan Pribićević was sent to North America where, in cooperation with the Serbian Embassy and immigrant organisations, he organised the transfer of volunteers to the Serbian Army. There was a total of 4,200 volunteers transferred and among them, apart from Serbs, there were 200 Croats and a smaller number of Slovenes. The organisation of volunteers in South America and dominions proved to be a failure. Although in Italy there were several thousand Yugoslav prisoners of war, the Italian government for political reasons disrupted their dispatch to the Thessalonica front, and only 260 of them arrived there.
The process of gathering volunteers from Russian detention was much easier. A centre for collection of volunteers was set up in Odessa and during February 1916 the first Serbian Volunteers Brigade was organised with 9,733 soldiers. These were practically exclusively Serbs from Bosnia and Herzegovina, Lika, and Vojvodina. By August the same year the division grew to 18,000 troops. After Romania joined the war, the division suffered losses of as many as 8,000 troops in battlefield against the Bulgarians in Dobruja. In Odessa the same summer the Second Serbian Volunteer division was formed with 11,169 troops, consisting not only of volunteers, but also other prisoners of war, so apart from Serbs (6,200) there was a significant number of Croats (3,144) and Slovenes (1,556). These two divisions merged to form the Serbian Volunteer Corps under the command of general Mihailo Živković. After the breaking out of the revolution in Russia in March 1917, and especially after the Bolshevik revolution in November 1917, a significant number of this formation dissipated. Finally, during the first months of 1918, a total of 12,500 volunteers arrived in Thessalonica. Volunteers arriving from Russia and the US were a valuable addition to the weakened units of the Serbian Army. Most volunteers in February 1918 formed the Yugoslav division which became part of the Second Army under the command of Commander Stepa Stepanović. The formation of this division had a political significance as it was to demonstrate that all Yugoslavs are taking part in the struggle for a unified country.