Editing Yugoslav Committee (section)

==Prelude==
===Florence meeting===
[[File:Map_Europe_alliances_1914-en.svg|thumb|Military alliances in Europe in 1914 {{legend|#83be58|[[Triple Entente]]}}{{legend|#b0a336|[[Triple Alliance (1882)|Triple Alliance]]}}]]

In October 1914, Serbian Prime Minister [[Nikola Pašić]] learnt the [[Government of the United Kingdom]] was considering expanding the alliance against the [[Central Powers]], which at that time consisted of the [[German Empire]] and [[Austria-Hungary]]. The UK intended to persuade Hungary to secede from Austria-Hungary and to persuade the [[Kingdom of Italy]] to abandon its neutrality so both countries could join the alliance of the UK, France, and Russia that was known as the [[Entente Powers]]. Pašić discovered the UK was considering guaranteeing Hungarian access to the [[Adriatic Sea]] through the [[Port of Rijeka]] and overland access to Rijeka over Croatian soil, and resolving the [[Adriatic Question]] satisfactorily for Italy. Pašić thought these developments, coupled with a potential UK–[[Kingdom of Romania|Romanian]] alliance, would threaten Serbia and jeopardise the Serbian objective of gaining access to the Adriatic.{{sfn|Boban|2019|p=17}}

In response, Pašić directed two [[Bosnian Serb]] members of the Austro-Hungarian [[Diet of Bosnia]],  [[Nikola Stojanović (politician, born 1880)|Nikola Stojanović]] and Dušan Vasiljević, to contact the émigré Croatian politicians and lawyers [[Ante Trumbić]] and [[Julije Gazzari]], in order to resist the pro-Hungarian British proposals and to create a Slavic alternative. Pašić proposed the establishment of a body that would cooperate with the Government of Serbia on the unification of South Slavs in a state that would be created through the expansion of Serbia. The policy of expansion was to be set and controlled entirely by Serbia, and the proposed body would carry out propaganda activities on its behalf.{{sfn|Boban|2019|p=17}} The four men met in [[Florence]], Italy, on 22 November 1914.{{sfn|Banac|1984|p=118}} In January 1915, [[Frano Supilo]], who was once a leading figure in the [[Croat-Serb Coalition]], the ruling political party of the Austro-Hungarian realm of [[Kingdom of Croatia-Slavonia|Croatia-Slavonia]],{{efn|Supilo co-founded the Croat-Serb Coalition with [[Svetozar Pribićević]] but left it following the [[Agram Trial]] and especially the {{ill|Friedjung Trial|hr|Friedjungov proces}} initiated by the coalition and Supilo was disappointed in a lack of support from the coalition. He was replaced by [[Ivan Lorković]] as co-chairman of the coalition. The move left Pribićević in effective control of the coalition.{{sfn|Boban|2019|p=9}}}} met with British foreign secretary [[Edward Grey, 1st Viscount Grey of Fallodon|Sir Edward Grey]] and Prime Minister [[H. H. Asquith]], providing them with the manifesto of the nascent Yugoslav Committee and discussing the benefits of South Slavic unification.{{sfn|Boban|2019|p=18}} The manifesto was co-written by Supilo and British political activist and historian [[Robert Seton-Watson]].{{sfn|Evans|2008|pp=159–160}}

===Niš Declaration===
{{main|Niš Declaration}}
[[File:Serbia1913.png|thumb|right|upright=0.7|Map of the [[Kingdom of Serbia]] before the [[World War I]]]]

The Serbian leadership considered World War I to be an opportunity for territorial expansion beyond the Serb-inhabited areas of the [[Balkans]]. A committee that was tasked with determining the country's war aims produced a program to establish a single South-Slavic state through the addition of Croatia-Slavonia, the [[Slovene Lands]], [[Serbian Vojvodina|Vojvodina]], [[Condominium of Bosnia and Herzegovina|Bosnia and Herzegovina]], and Dalmatia.{{sfn|Pavlowitch|2003a|p=29}} Pašić thought the process should be implemented through the addition of new territories to Serbia.{{sfn|Banac|1984|pp=118–119}} On 7 December, Serbia announced its war aims in the [[Niš Declaration]].{{sfn|Lampe|2000|pp=102–103}} The declaration called on South Slavs to struggle to liberate and unify "unliberated brothers",{{sfn|Ramet|2006|p=40}} "three tribes of one people"&nbsp;– referring to  Serbs, Croats, and Slovenes.{{sfn|Lampe|2000|pp=102–103}} This formulation was adopted instead of an explicit goal of territorial expansion as a way to attract support from South Slavs living in Austria-Hungary. The Serbian government wanted to appeal to fellow South Slavs because it feared little material support would be delivered from its Entente Powers allies as it became clear the war would not be short.{{sfn|Lampe|2000|pp=102–103}} Serbia assumed a central role in the state-building of the future South Slavic polity, with support from the major Entente Powers.{{sfn|Pavlović|2008|p=70}}

Supilo initially assumed the Niš Declaration meant Serbia was fully supportive of his ideas on the method of unification. He was convinced otherwise by Russian foreign minister [[Sergey Sazonov]], who informed Supilo that Russia only supported the creation of Greater Serbia.{{sfn|Boban|2019|p=19}} As a result, Supilo and Trumbić did not trust Pašić, and considered him a proponent of Serbian hegemony.{{sfn|Ramet|2006|pp=41–42}} Despite the mistrust, Supilo and Trumbić wanted to work with Pašić to further the aim of South-Slavic unification. Pašić offered to work with them towards the establishment of a Serbo-Croat state in which Croats would be given some concessions, an offer they declined.{{sfn|Banac|1984|pp=118–119}} Trumbić was convinced the Serbian leadership thought of unification as a means to conquer neighbouring territories for Serbian gain.{{sfn|Banac|1984|p=119}}

Trumbić and Supilo found another reason to distrust Pašić when Pašić dispatched envoys to address Sazonov's opposition to the addition of Roman Catholic South Slavs to the proposed South Slavic union. The envoys wrote a memorandum claiming Croats only inhabit the north of Central Croatia, and that the regions of Slavonia, [[Krbava]], [[Lika]], [[Bačka]], and [[Banat]] should be added to Serbia, as well as the previously claimed Dalmatia, and Bosnia and Herzegovina.{{sfn|Boban|2019|pp=19–20}} Trumbić and Supilo became convinced that because of the Government of Serbia's expansionist policy, the proposed unification would be perceived within Croatian-inhabited areas of Austria-Hungary as a Serbian conquest rather than as a liberation. They decided to proceed with caution, gather political support abroad, and to refrain from the establishment of a Yugoslav Committee until Italy's entry into the war became certain.{{sfn|Boban|2019|p=17}}

===Treaty of London===
{{main|Treaty of London (1915)}}
[[File:Promised Borders of the Tready of London.png|thumb|right|Territories promised to Italy by the Entente in the [[South Tyrol]], the [[Austrian Littoral]], and [[Dalmatia]] (tan), and the [[Snežnik (plateau)|Snežnik Plateau]] area (green).]]

The Entente Powers ultimately concluded an alliance with Italy by offering it large areas of Austria-Hungary that were inhabited by South Slavs, mostly Croats and Slovenes, along the eastern shores of the Adriatic Sea. The offer was formalised as the [[Treaty of London (1915)|1915 Treaty of London]], and caused Trumbić and Supilo to reconsider their criticism of Serbian policies. This was because they saw potential Serbian war success against Austria-Hungary as the only realistic safeguard against Italian expansion into the Slovene-and-Croat-inhabited lands. Supilo was convinced Croatia would be partitioned between Italy, Serbia, and Hungary if the Treaty of London was to be implemented.{{sfn|Banac|1984|pp=119–120}}

The matter became closely related to the Entente's simultaneous efforts to obtain an [[Bulgaria during World War I|alliance with Bulgaria]], or at least to secure its neutrality, in return for territorial gains against Serbia.{{sfn|Robbins|1971|p=574}} As compensation, Serbia was promised territories that were within Austria-Hungary at the time: Bosnia and Herzegovina and an outlet to the Adriatic Sea in Dalmatia. Regardless of the promised compensation, Pašić was reluctant to accede to all of the Bulgarian territorial demands, especially before Serbia had secured the new territories.{{sfn|Robbins|1971|pp=565–570}} Supilo obtained British support for plebiscites in Bosnia and Herzegovina and Dalmatia so the populace of those territories would decide on their own fate rather than Britain supplying guarantees of westward territorial expansion to Serbia.{{sfn|Mastilović|2012|p=277}} Crucially, Serbia received Russian support for its dismissal of the proposed land swap.{{sfn|Robbins|1971|pp=565–570}}