Creation of Yugoslavia

Yugoslavism

During the First World War, pressure developed in the parts of Austria-Hungary inhabited by its South Slavic population—the Croats, the Serbs, the Slovenes, and the Muslim Slavs (Bosniaks)—to support trialist reform,^[1] or the establishment of a common South Slavic state independent of the empire. This common state was meant to be achieved through the realisation of the ideas of Yugoslavism and unification with the Kingdom of Serbia.^[2] The concept was meant as an expression of the notion that the South Slavs belong to a single "race", were of "one blood", and had one shared language, it was considered neutral regarding the possibility of centralised or decentralised government in a common state.^[3]

The proponents of the political union pursued different forms of Yugoslavism. Unitarist or integral Yugoslavism and federalist Yugoslavism were the two major categories. The former denied the existence of separate nations or sought to supersede them by introducing a single Yugoslav nation. The federalists acknowledged the existence of separate nations and wanted to accommodate them in a new political union through a federation or another system affording various South Slavic nations political and cultural autonomy.^[4]

National Council of Slovenes, Croats and Serbs

On 5–6 October, in the final weeks of the First World War, representatives of political parties representing the Croats, the Serbs, and the Slovenes living in Austria-Hungary established the National Council of Slovenes, Croats and Serbs as a representative body aiming to achieve independence from the empire. On 18 October, the body declared itself the central organ of the newly proclaimed State of Slovenes, Croats and Serbs encompassing the Slovene Lands, Croatia-Slavonia, Dalmatia, and Bosnia and Herzegovina.^[5] The National Council elected the leader of the Slovene People's Party (SLS) Anton Korošec its president. The National Council had two vice presidents: One was Svetozar Pribičević—the leader of the Croat-Serb Coalition (HSK), the ruling party in Croatia-Slavonia; Another vice president was Ante Pavelić, the leader of the Mile Starčević faction of the Party of Rights (SSP).^[6]

Yugoslav Committee

On 26 October 1918, the National Council authorised the Yugoslav Committee, an ad hoc group of emigrés led by Ante Trumbić promoting the interests of the Croats, Serbs, and Slovenes living in Austria-Hungary during the war, to speak on behalf of the council.^[7] In 1917, the Yugoslav Committee had established contacts with the government of Serbia led by the prime minister Nikola Pašić and they produced the Corfu Declaration on the shared objective of unification of the South Slavs in a parliamentary constitutional monarchy. The declaration left unresolved the choice between a unitary state advocated by Pašić or a federation advocated by Trumbić.^[5] He held that a federal constitution of the new state to ensure that Serbia or Serbs would not dominate future common governments.^[8]

Regardless of the differences, the Yugoslav Committee leadership applied a cautious approach in its relationship with Serbia. On one hand, they learned of the Treaty of London whereby the Allies offered Italy substantial Austro-Hungarian territories with sizeable Croat and Slovene populations and realised that political alignment with Serbia might be the only way to ensure that all Croats and all Slovenes live in a single country. On the other hand, the Yugoslav Committee also learned that the Allies had offered Serbia territories, including the part of Dalmatia not already promised to Italy, as well as Slavonia, Bosnia and Herzegovina and Bačka. This led the leaders of the Yugoslav Committee to conclude that Croatian lands, referred to as the Triune Kingdom, might be divided among Italy and Serbia with the remainder potentially offered to Hungary in a plot to break-up the Austro-Hungarian state.^[9]

Kingdom of Serbia

Serbia considered the war an opportunity for territorial expansion. A committee tasked with determining the country's war aims produced a programme to establish a wider South Slavic state by adding the South Slav-inhabited parts of the Habsburg lands—Croatia-Slavonia, Slovene Lands, Vojvodina, Bosnia and Herzegovina, and Dalmatia—to Serbia.^[10] Following several military setbacks in the Serbian campaign, the National Assembly of Serbia announced the unification of the South Slavs as its national war aim in its December 1914 Niš Declaration.^[11] The declaration was meant to attract support from South Slavs living in Austria-Hungary. The government was motivated to appeal to the fellow South Slavs as it feared little material support was coming from the Triple Entente allies.^[12] Pašić wanted to abandon the Niš Declaration in 1916 and reduce the wartime objectives to liberation of Serbian territory and gaining control over areas inhabited by ethnic Serbs, but he was overruled by the Prince Regent Alexander.^[13]

On 29 September 1918, in the final stages of the war, Bulgaria signed the armistice of Salonica following the collapse of its defensive positions at the Macedonian front and withdrew from the war. The Allied Army of the Orient, commanded by French General Louis Franchet d'Espèrey, rapidly advanced north as a result, recapturing ground that had been lost to the Central Powers in the Great Retreat from Serbia in 1915. By 1 November, the Serbian First Army under vojvoda Petar Bojović and the French Armée d'Orient, led by General Paul Prosper Henrys, reached Belgrade. Once there, the troops stopped to rest, with only minimal forces deployed across the Danube and Sava rivers, which represented Serbia's pre-war border with Austria-Hungary. The liberation of Serbia was largely complete.^[14]

State of Slovenes, Croats and Serbs

On 29 October, the Croatian Sabor voted on a series of proposals by Pribićević and Pavelić who commanded the majority in the parliament. Sabor declared the end of ties of Austria-Hungary and the Triune Kingdom of Croatia, claiming Dalmatia and the city of Rijeka, previously organised as the Corpus separatum. Then it declared that the independent Croatia would enter the new State of Slovenes, Croats and Serbs established at the South Slav-inhabited territory previously ruled by Austria-Hungary, noting that the country would ultimately lay claim to the territory extend from the Soča River to the city of Thessaloniki at the Aegean Sea coast. Finally, the Sabor delegated its powers to the National Council of Slovenes, Croats and Serbs. Regional councils, subordinate to the National Council, were established in Ljubljana, Sarajevo, and Split to represent Slovenia, Bosnia and Herzegovina, and Dalmatia.^[15] While the Slovene and Bosnia-Herzegovinian councils were formed in agreement with the central Zagreb-based National Council on 30 October, the Dalmatian body was set up without consulting Zagreb on 2 November.^[16]

On 31 October, the National Council declared the State of Slovenes, Croats and Serbs was ready to form a common state with Serbia.^[15] However, the National Council was divided on the method of the unification and the form of the unified country's government. While Pribićević led the group advocating for an unconditional and rapid unification, Croat members of the body were being more cautious about potentially dominant position of the Serbs in the unified state and the risk of individuality of Croats.^[17] On 1 November, Korošec invited Trumbić and Pašić to talks in Geneva.^[18] He spent most of November 1918 abroad, delegating running of the National Council and governing the State of Slovenes, Croats and Serbs to Pavelić and Pribićević.^[19] Two days later, Korošec unsuccessfully asked the Allied Powers to formally recognise the State of Slovenes, Croats and Serbs. The only recognition of the state was by Serbia five days later.^[20]

At the time, social disorder associated with the Green Cadres and widespread belief, especially prevalent in the northern Croatia, that the dissolution of Austria-Hungary would bring the end of bureaucracy and redistribution of wealth,^[21] attained the characteristics of a revolution.^[22] This forced the National council to institute court-martial,^[23] and request Serbian government to deploy the Royal Serbian Army to quell the unrest on 5 November.^[24] The National Council dispatched Laza Popović [sr], Pribićević's brother Valerijan, and Dragutin Perko to Belgrade with instructions to request Serbian army units be deployed to the regions of Syrmia and Slavonia east of Osijek–Slavonski Šamac railway line and placed under control of the National Council once they arrive.^[23] Regardless of the request, the Serbian government instructed the Serbian First Army to capture Banat and Bačka and the Second Army to advance west to Croatia, Bosnia and Herzegovina, and Dalmatia; Serbian troops started heading towards these regions on 5 November.^[25] By that time, Austria-Hungary had surrendered and the Italian armed forces advanced into Istria and landed in Dalmatia in Zadar to occupy the territories promised to Italy under the 1915 Treaty of London within the framework of the Allied occupation of the eastern Adriatic.^[26]

Geneva conference

The representatives of the National Council supported by the Yugoslav Committee met with Pašić and representatives of the Serbia's parliamentary opposition parties in Geneva on 6–9 November. The conference negotiated the details of the future unified state of the South Slavs. The agreement known as the Geneva Declaration defined the new state as a confederation having limited central government established through cooperation of the Kingdom of Serbia and the State of Slovenes, Croats and Serbs as equal partners. The document also invited the Kingdom of Montenegro to join the process of unification. Days later, Serbian government repudiated the Geneva Declaration.^[27][28] Historian Ivo Banac assessed acceptance of the Geneva Declaration and its subsequent repudiation as Pašić's tactic designed to commit the National Council and the Yugoslav Committee to speedy unification while relying on Pribićević to undermine Korošec's authority within the National Council.^[29]

On 13 November, when the Armistice of Belgrade was signed, Lieutenant Colonel Dušan Simović arrived in Zagreb as the representative of the Serbian army supreme command.^[30] Simović was welcomed by Pribićević, Pavelić, Ivan Lorković, and others. On this occasion, Lorković or Pavelić (sources disagree) spoke of the State of Slovenes, Croats and Serbs, as an entity independent of Serbia, united with Serbia in a federation. Simović was tasked with threatening the annexing some territories of the State of Slovenes, Croats and Serbs if the National Council in Zagreb were uncooperative. Therefore, Simović pointed out that Serbia was victorious in the war and was promised Slavonia to the Osijek—Đakovo—Šamac line, Bosnia and Herzegovina, and Dalmatia south of Cape Planka, adding that it would take those territories unless the unification was carried out.^[30][31] This caused Pavelić to walk back the idea of a federation.^[31] Simović's threat was interpreted as a credible threat to establish Greater Serbia, and leave a rump Croatia outside the new South Slavic State.^[32] Historian Charles Ingrao and philosopher and legal scholar Lazar Vrkatić [sr] interpreted the Simović's speech as blackmail on behalf of the army and the Regent, demanding capitulation to accept speedy unification as annexation, leaving determination of the system of government for a later date.^[33] On 14 November, Pašić informed Trumbić and Korošec that the Geneva Declaration was rejected by the Serbian government and by the Regent.^[34][35] According to Ingrao and Vrkatić, the Regent undermined the Geneva Declaration because it deprived Serbia of the role of the sole leader of the political unification of the South Slavs and did not guarantee the House of Karađorđević the right to rule over the entire country.^[33]

Lipošćak affair

The urgency of unification increased for the National Council as security deteriorated and due to the advance of the Italian forces that captured Rijeka and were advancing through Carniola, reaching the vicinity of Ljubljana.^[36] On 19 November, Vice Admiral Enrico Millo was appointed the governor of Italy's newly established Governorate of Dalmatia.^[37] On 22 November, one day before the scheduled National Council meeting to debate the unification, Simović reported uncovering of the plot aimed at establishing councils composed of workers, peasants and soldiers in place of the National Council. The alleged ringleader of the coup d'état was former Austro-Hungarian General of the Infantry Anton Lipošćak who had just returned to Zagreb after the armistice.^[38] After Lipošćak's arrest, the press speculated that the conspiracy must involve disgruntled Austro-Hungarian officers, that the conspirators were supported by Stjepan Radić of the Croatian Peoples' Peasant Party (HSS), or allied with Italian and/or Hungarian interests, as well as that Lipošćak was a Bolshevik or pretending to be a Bolshevik aiming to restore the Habsburg Empire.^[39] Some press reports specified that the conspirators planned to arrest the National Council to prevent its work towards unifying the South Slavs.^[40] In January 1919, Lipošćak was cleared of all charges.^[41] Nonetheless, the affair provided Pribićević with a pretext to demand urgent unification with Serbia for security reasons.^[42]

Unification decision and instructions

The central committee of the National Council convened in Zagreb on 23 November. The meeting, chaired by Pribićević, assessed the overall situation as critical, demanding immediate action to avoid chaos in the country. The committee also discussed a provincial Dalmatian National Council's resolution to urge the central committee of the National Council to complete the unification with Serbia without delay. The resolution, signed and presented by Ivo Krstelj and Josip Smodlaka cautioned the National Council that, unless the unification is decided upon within five days, Dalmatia would join Serbia unilaterally.^[43] The Dalmatian resolution and ultimatum were motivated by the fear of further Italian territorial conquest.^[44] The central committee was further informed that the Sarajevo-based National Council supported the Dalmatian government's resolution, and that Bosnia and Herzegovina would follow their example.^[45] During the second day of the central committee meeting, on 24 November, an assembly was convened in the town of Ruma in Syrmia. The unelected assembly where the largest towns in the region were not represented, adopted a resolution stating that the region of Syrmia would secede from Croatia-Slavonia and be annexed to the Kingdom of Serbia unless the National Council in Zagreb decided positively on creation of a unified state with Serbia.^[46]

The most siginificant opposition to the speedy unification at the meeting came from Radić as he believed the unification was proposed against the will of the majority of Croats. At this point, Radić delivered his subsequently often referenced speech meant as one final warning against the reckless approach of the National Council to the unification, comparing their step into uncertain territory to wandering "like drunken geese into a fog". He then proposed an alternative plan calling for a confederal state led by three regents. Radić proposed they should be the king of Serbia, the Ban of Croatia, and the president of the Slovene National Council, who would appoint only three common ministers—foreign affairs, defence, and food distribution ministers. Radić was rejected by the National Council as "extreme separatism".^[47] Namely, his proposal foresaw four autonomous state governments in Slovenia, Croatia, Serbia, and in Montenegro; as well as provincial autonomous governments in Bosnia and Herzegovina, Dalmatia, and Vojvodina all accountable to state or provincial diets.^[48]

The central committee pursued immediate unification with Serbia. It appointed a 28-strong delegation tasked with travelling to Belgrade to arrange for the unification, and adopted instructions to the delegation.^[49] Namely, the delegation was instructed to insist on a federal system of government in the new country.^[50] The instructions required the delegation to insist on adoption of the national constitution by a two-thirds majority vote, designated the Regent a provisional ruler until the constitution is in place, named foreign affairs, defence, railway and maritime transport, finances and post as the domain of the central government and prescribed preservation of all existing administrative and judicial bodies in place. The plan with the instructions was adopted by majority, with only Radić and Dragutin Hrvoj [hr] dissenting.^[51][52] The delegation comprised Frane Barac, Izidor Cankar, Luka Čabrajić, Mate Drinković, Šćepan Grđić, Halid Hrasnica [cs], Vitomir Korać, Korošec, Albert Kramer, Anton Kristan [sl], Matko Laginja, Lorković, Edo Lukinić, Savo Ljubibratić, Ivan Paleček, Pavelić, Živko Petričić [hr], Dušan A. Popović, Pribićević, Radić, Smodlaka, Vasa Stajić, Joso Sunarić, Hamid Svrzo [cs], Janko Šimrak, Vojislav Šola, Ante Tresić Pavičić, and Trumbić.^[53]

On 26 November, two days after the delegation members were appointed, there was a debate on the date when the delegation would actually go to Belgrade. The meeting concluded with no formal agreement reached. Pribićević asked the members who supported his views to remain in place after the meeting and the group then decided that the delegation would go to Belgrade the next day. At the same time, the group expelled Radić from the National Council's central committee.^[54]

Vojvodina

Serbs living in Bačka, Banat, and southern Baranya (collectively referred to as Vojvodina) were predominantly supportive of leaving Austria-Hungary, but were divided on the method—through the National Council in Zagreb or through close ties with Serbia.^[55] Early support for the National Council was replaced by the view that the territories should be annexed by Serbia outright.^[56] On 3 November, the Serbian National Committee was established in Novi Sad to facilitate the annexation.^[57] A competing movement set up the short-lived autonomous Banat Republic, nominally within Hungary, was declared in the eponymous region.^[58] On 1 November, the Banat National Council proclaimed the republic in Timișoara, relying on support from the Hungarian and German communities.^[59] In early November, Serbian troops continued to advance north across Vojvodina, capturing the territory and displacing civilian and self-proclaimed authorities.^[60]

On 17 November, a conference was convened in Novi Sad in compliance with instructions from the Serbian Government and elections were announced for the Great People's Assembly of Serbs, Bunjevci and other Slavs in Banat, Bačka and Baranja. The purpose of the assembly was to consult the Slavic population of Vojvodina for their opinions.^[61] The elections produced 757 delegates to the assembly claiming to represent Banat, Bačka and Baranja. Those included 578 Serbs, 84 Bunjevci, 3 Šokci, 2 Croats, 62 Slovaks, 21 Ruthenians, 6 Germans and a single Hungarian. The non-Slavic population of Vojvodina, which exceeded 60% of the total, was represented in the Assembly by 1% of the delegates.^[62] The assembly held in Novi Sad on 25 November produced two resolutions. The first resolution, which was quickly accepted by the Serbian government, specified that the territory was a part of Serbia and formally asked the Government of Serbia to represent Banat, Bačka and Baranja at the upcoming Paris Peace Conference.^[63][56]

The second resolution announced the establishment of a regional National Council to administer the territory and that the new border was determined by the army's advance. The resolution was in breach of an earlier decision by the Allies determining that only the Paris Peace Conference may determine national borders. According to Ingrao and Vrkatić, the second resolution effectively upheld application of the existing (Hungarian) law in Vojvodina, but the Serbian Government recognised neither the National Council nor laws other than those of Kingdom of Serbia as effective in Vojvodina.^[64] According to the two, the annexation of Vojvodina was completed in a manner meant to affirm the role of the Royal Serbian Army and that the Regent Alexander was the only relevant factors in the unification of the South Slavs.^[65]

Montenegro

In early 1916, king Nikola and most of the government left Montenegro fleeing an Austro-Hungarian offensive.^[66] The remaining government ministers declared a new government and surrendered to Austria-Hungary, attributing the surrender to king's departure.^[67] Failing to obtain international support for the restoration of Montenegro's independence during the Austro-Hungarian occupation, Nikola gradually shifted his approach to Yugoslavism, advocating a South Slavic federation or confederation, with Montenegro as one of its constitutive elements.^[68] Before the end of the war, former Prime Minister Andrija Radović emerged as a leading advocate for interation of Montenegro into Serbia. In collaboration with Serbian government, he established the Montenegrin Committee for Unification [sr] in 1917.^[69] The two opposing political camps both supported political unification of the South Slavs but differed in opinions on level of centralisation of the state and historian Marko Attila Hoare described the groups as the annexationists and the autonomists.^[70]

In September 1918, the Entente powers started their advance at the Salonica front, reclaiming the territory of the occupied Serbia. As a part of the offensive, a task force known as the Adriatic Troops (Jadranske Trupe) was diverted into Montenegro ahead of supporters of Nikola or Italian forces,^[71] perceived as a threat by Serbia due to Italy's demand for the establishment of an Italian condominium in Montenegro, excluding a Serbian presence.^[72] The Adriatic Troops, led by Colonel Dragutin Milutinović [sr], were tasked by the Regent with preventing the return of Nikola by any means. Accompanied by Spasojević, a member of the Montenegrin Committee, and Svetozar Tomić, head of the Montenegrin section of the Serbian Foreign Ministry, Milutinović established the Central Executive Committee for the Unification of Serbia and Montenegro on 28 October. This committee, comprising Spasojević, Tomić, and Berane mayor Milosav Raičević, was tasked with organizing a popular assembly and establishing the rules for the election of assembly delegates.^[71]

The rules, adopted on 7 November, stipulated that elected delegates would convene in Podgorica,^[73] chosen as the venue because the capital, Cetinje was a stronghold of Nikola's supporters beyond control of the assembly organisers.^[74] The annexationists and the autonomists known as the Whites and Greens respectively (after the colour of papers the candidate lists were printed on argued over legality and legitimacy of the election. The Whites objected because the election rules were not formulated by any Montenegrin legislative body and because they contravened the existing laws. The whites thought the election illegitimate due to lack of oversight of the voting and absence of a minimum voter turnout requirement. The Greens saw the process as a form of plebiscite that legitimised the new assembly.^[75] 165 delegates in total were to be elected.^[76] The election, held on 19 November, resulted in a significant assembly majority for the Whites.^[77] There were allegations that the Royal Serbian Army obstructed the Greens from returning from abroad and interfering with the electoral process.^[75] French authorities prevented Nikola from returning to Montenegro from his exile in Neuilly-sur-Seine.^[72] The Podgorica Assembly convened on 24 November. Two days later it voted to remove Nikola from the Montenegrin throne and to decide that Montenegro and Serbia would be united under Serbia's ruling Karađorđević dynasty, joining the common state of the "three-named people" (Serbs, Croats, and Slovenes). Further decisions were to elect an executive committee to coordinate the unification work, and to send notices of the resolution to Nikola, the Serbian government, as well as allied and neutral countries.^[78] The decision was unanimously adopted, with three delegates absent from the vote.^[77] Ingrao and Vrkatić characterised the process as an annexation of Montenegro to Serbia.^[79]

Bosnia and Herzegovina

While no annexation of Bosnia and Herzegovina by the Kingdom of Serbia took place in the process of political unification of the South Slavs, there were pressures on the government of Bosnia and Herzegovina led by Atanasije Šola [sr] to embark on such a project. There was a significant grassroots pressure on Šola to request annexation by Serbia. Specifically, 42 out of 54 district-level national councils established in the final phase of dissolution of Austria-Hungary voted to support initiatives to proclaim unification of Bosnia and Herzegovina with Serbia. Most of such initiatives came from the region of Bosanska Krajina, especially the town of Banja Luka. Serbian government instructed the Royal Serbian Army to assist the government of Bosnia and Herzegovina in its pursuit of unification, and put pressure on Šola's government, only appointed by the National Council on 30 October, to unilaterally declare unification with Serbia.^[80]

According to Ingrao and Vrkatić, Šola's resistance to the pressure stemmed from support by the Regent Alexander. Namely, the Regent thought it was necessary to have Bosnia and Herzegovina join the political union of the South Slavs through the State of Slovenes, Croats and Serbs, to ensure that Croatia joins the union as well. He believed that Croatia would not have joined the new state unless it was done together with Bosnia and Herzegovina regardless of Italian threats. Ingrao and Vrkatić concluded that this was the reason why the Serbian armed forces in Bosnia and Herzegovina did not introduce military administration of the land even though it might have been easier to introduce than in Vojvodina or Montenegro—finding the Regent's motivation in his narcissism and conviction that a purely Serb state was too small for him as a ruler.^[81]

Allied occupation and recognition

Yugoslavia did not receive an immediate diplomatic recognition by the Allied Powers. Instead, the Yugoslav delegation to the Paris Peace Conference was formally treated as that of the Kingdom of Serbia. The United States initiated the procedure of diplomatic recognition in February 1919, while the remaining allies continued to withhold it on insistence of Italy. Italian temporary boycott of the conference due to an inter-Allied dispute led to a wider recognition of Yugoslavia on the occasion of signing of the Treaty of Versailles in June 1919.^[89]

Regardless of the recognition, the allied occupation of the Adriatic coast established immediately after the armistice continued, organised in four zones where Italy, the United States, France, and the United Kingdom had formal command over allied forces.^[90] British involvement ended when allied troops, including Italian, were withdrawn from Rijeka in response to arrival of Italian irredentist and nationalist Gabriele D'Annunzio with troops loyal to him personally in September 1919. Once there, D'Annunzio proclaimed the establishment of Italian Regency of Carnaro that lasted for fifteen months.^[91] Military rule persisted in parts of the Italian and French zones until December 1920.^[92][93] The US mission left in September 1921, ending the occupation.^[94]

Borders and population

The peace conference determined a portion of Yugoslav borders. The frontier with the Republic of German-Austria through the Treaty of Saint-Germain-en-Laye in September 1919.^[95] The treaty followed the Austro-Slovene conflict in Carinthia where Slovene leaders including Korošec leveraged Serbian (later Yugoslav) military to enforce territorial claims in parts of Carinthia and Lower Styria, occupying the Carinthian capital of Klagenfurt and using military to assert control in Styrian city of Maribor in the Marburg's Bloody Sunday. The fighting was ended by the treaty and the border dispute resolved through the 1920 Carinthian plebiscite.^[96]

The Bulgarian–Yugoslav border was determined in November 1919 through the Treaty of Neuilly-sur-Seine.^[89] The Romanian–Yugoslav frontier resulted from the occupation of Banat, followed by partition of the region by the Allies who turned its eastern part to Romania.^[58] The Allied decision was made in June 1919 and Romania accepted it only six months later, relinquishing its earlier claim to entire Banat.^[97] Yugoslav border with Hungary was settled under the Treaty of Trianon in June 1920. The treaty upheld Yugoslav annexation of Vojvodina and seizure of Međimurje and Prekmurje with some border adjustments.^[95]

The problem of establishing the border between Italy and Yugoslavia—referred to as the Adriatic question—including the Fiume question regarding the status of the city of Rijeka became a major point of dispute at the Paris Peace Conference.^[98] Since the Yugoslav and the Italian diplomats could not agree the border between the countries, the Allies instructed them to settle the issue through direct negotiations after the Paris Peace Conference.^[99] Negotiations took place in November 1920, resulting in the Treaty of Rapallo.^[100] The treaty defined the border giving Italy Istria, the Julian March, the city of Zadar and several islands.^[101] The treaty also established the independent Free State of Fiume.^[102]

Yugoslavia had its first census taken in 1921, after its borders were defined. It was determined to have just over 12 million inhabitants and approximately two-thirds of that number were living in the former Austro-Hungarian lands. Belgrade, the country's capital was slightly bigger city than Zagreb—both having populations of about 110,000.^[89] The country was ethnically diverse. Just under 39% of that number were Serbs or Montenegrins, nearly 24% were Croats, and 8.5% were Slovenes.^[103] Three-quarters of the population are living by farming. Literacy rate varied by province, from nearly 100% in Slovenia to 35% in Serbia and the country was among the lowest-ranking in Europe in terms of literacy rate.^[89]

Interim bodies

The first Yugoslav government was appointed by the Regent alone. The principal political parties started negotiations of the government on 11 December 1918 and came to an agreement that Pašić should be the prime minister. Regardless of the agreement, on 20 December, the Regent appointed Protić the prime minister.^[104] Even though Protić belonged to the (People's Radical Party, NRS), 11 of 17 government ministers were drawn from the leading Serbian centrist party, the Democratic Party (DS).^[105]

An interim parliament was established as the Temporary National Representation (Privremeno narodno predstavništvo, PNP) by Regent Alexander's decree of 24 February 1919.^[106] It convened for the first time in Belgrade on 1 March.^[107] According to Banac, the delay was intended to ensure that the government was free to implement decisions designed to centralise the country without interference from the parliament. The government contested the PNP's right to enact any legislation, except on the procedure of election of the Constituent Assembly and determination of its agenda.^[106] The PNP was composed generally of people who had served on a legislative or consultative body.^[108] Most of its 294 members were not elected but appointed.^[106] The National Council did not take up the selecting of its representatives.^[109] Instead, a Regent's political ally drew up a list of representatives for appointment on the authority of the Regent.^[110] The elections for 419 members of the Constitutional Assembly were held in November 1920.^[111] The newly elected assembly adopted the Vidovdan Constitution in June 1921 confirming a centralist system of government of the interwar Yugoslavia. The constitution was adopted by a simple majority of thirteen votes.^[112]

Economic integration and unrest

Immediately after the political unification, the government faced problems of economic integration of the country since various provinces had greater trade volume with other markets than with each other due to political divisions of the era. Policies adopted to achieve economic integration often caused mutual resentments by various ethnic groups comprising Yugoslavia as well as political problems—as in case of introduction of the Yugoslav krone as an interim currency in the process of establishment of a single Yugoslav currency, and in case of the 1919 land reform.^[113] Serbian industry, concentrated in and around Belgrade, suffered significant war damage which was slow to recover from due to war-damaged, comparably underdeveloped railway network in the area. These problems led to increased unemployment and low wages in the industrial sector that contributed to popularity of the nascent Communist Party of Yugoslavia, as well as allowed Croatia's industry, largely centered on Zagreb, to outgrow that of Serbia. While the two were of comparable size before the war, Zagreb's industrial output became four times greater than that of Belgrade by 1926.^[114]

Social unrest was widespread in the country in the initial period following the creation of Yugoslavia. Only days after the proclamation of unification, there was a large anti-monarchy protest in Zagreb suppressed by violence. In the period until 1920, Croatian countryside saw widespread violence—some of it ethnic, but mostly looting of large estates and shops—as well as the 1920 Croatian Peasant Rebellion triggered by an army campaign to brand draft animals. More significant violence was seen in Kosovo where there was a series of uprisings by ethnic Albanians known as the Kachak Movement. In response the government deployed the army to the area and launched a campaign of settlement of Serbs and Montenegrins to land confiscated from the rebels. In Bosnia and Herzegovina, there was widespread ethnic violence in which Bosnian Serbs killed or evicted several thousand Muslim Bosniaks and seized their land. Ethnic violence against Muslim population also took place in Sandžak region of Montenegro such as the Šahovići massacre. Elsewhere in Montenegro, the pro-independence faction of Greens launched the ultimately unsuccessful Christmas Uprising in 1919. The next year, Orthodox Church structure in Montenegro lost its de facto autonomous position and became integrated in the Serbian Orthodox Church.^[115]