ЗВО, ZVO) is an elected consultative sui generis body which constitutes a form of cultural self-government of Serbs in the eastern Croatian Podunavlje region.

The body was established in the initial aftermath of the Croatian War of Independence as a part of the international community's efforts to peacefully settle the conflict in self-proclaimed Eastern Slavonia, Baranya and Western Syrmia.

The Joint Council of Municipalities is not an autonomous administrative unit but a form of cultural autonomy in conformity with relevant Croatian and international law including provisions on local government cooperation.

SAO Eastern Slavonia, Baranja and Western Syrmia was ethnically cleansed of its non-Serb population and it became part of the self-proclaimed Republic of Serbian Krajina.

Several Serb military and political officials, including Milošević, were later indicted and in some cases jailed for war crimes committed during and after the conflict in Eastern Slavonia.

[11] Contrary to Krajina, the international community under the United States leadership opposed military solution in Eastern Slavonia and insisted on reintegration based on preservation of the multi-ethnic character of the region.

The concept of a free municipal association was used by Serb nationalists in Croatia at an early stage of the conflict in the formation of the self-proclaimed Republic of Serbian Krajina.

At that time Croatian Serb politician Jovan Rašković argued for the creation of the "integral region" via the establishment of an Association of Municipalities.

[16] While the Croatian legal system at the time formally permitted such a form of municipal organization the move was perceived as highly controversial and led to some of the first clashes.

As any such cooperation might have been perceived as antagonistic and controversial and therefore prevented, the right to establish a joint council of municipalities was explicitly included in the Erdut Agreement.

[17] In the second half of the year, they asked Transitional Administrator Jacques Paul Klein to keep the region as an Association of Serb Municipalities with executive powers.

This letter was perceived as a precondition for successful end of the UNTAES mission's mandate and it was signed by then Deputy Prime Minister Ivica Kostović.

In it Croatian Government reassured the United Nations Security Council of its intention to organize free and fair local elections in which Serbs and other ethnic communities in the region will be enabled to participate.

[17] The founding Charter of the organization was signed by Jure Radić and Miloš Vojnović on 15 July 1997 at the Osijek Airport in the presence of UNTAES Head Jacques Paul Klein.

[17] In early August the president of Committee for Civic, Human and Minority Rights, Branko Jurišić, complained to representatives of the European Union Monitoring Mission that the council had not been registered in Zagreb although it had already begun to carry out most of its tasks on the ground.

[17] 31st Plenary Meeting Venice Commission on 20–21 June 1997 adopted its Memorandum on the revision of the Croatian constitutional law of Human Rights and Rights of Minorities in which it recommended "inclusion of elements of the "Letter of intent of the Government of the Republic of Croatia on the peaceful reintegration of the region under transitional administration" in the Revised Constitutional Law".

[20] Members of Croatian Government were divided whether to support the request for this type of registration or not which blocked the council from participation in some forms of official communication and standards and fixed streamlines of public funding.

[20] Upon the insistence from Serb representatives and the Venice Commission temporary solution was reached until the enactment of the new Constitutional Act on the Rights of National Minorities in the Republic of Croatia in 2003.

The original proposal by the Cabinet of Jadranka Kosor to lawmakers included constitutional amendment accepting requests for a changed legal standing with the following provision: In the area of Vukovar-Syrmia and Osijek-Baranja County and in accordance with the Basic Agreement on Eastern Slavonia, Baranja and Western Sirmium of 12 November 1995.

(Erdut Agreement) and the Letter of Intent of the Croatian Government of 13 January 1997., the Joint Council of Municipalities functions as a legal entity.

Milorad Pupovac, MP of the Serb national minority condemned the MPs who were willing to recognize the full independence of Kosovo, while objecting to the autonomy of the local Serbian community.

[22] President of the Independent Democratic Serbian Party Vojislav Stanimirović condemned MP Vesna Pusić (then-President of the National Committee for Monitoring Accession Negotiations with EU).

[23] At the ZVO Emergency Council Meeting on the next day then President Dragan Crnogorac condemned statements by Pusić, Ingrid Antičević-Marinović, Josip Leko and Zoran Vinković.

Joint Council of Municipalities called press conference related to protests which attracted the highest media interest since the end of the UN led reintegration in 1997.

[30] At the conference Milorad Pupovac called politicians "not to play with fire" and warned then president of the Croatian Democratic Union Tomislav Karamarko not to interfere into legal field of the interpretation of the Constitutional Act on the Rights of National Minorities in the Republic of Croatia.

[31] Since the 2016 elections new Prime Minister Andrej Plenković is trying to ease growing political tensions by controlling his own party and leading it towards more moderate course.

[32] However, financial and social pressure which the Joint Council of Municipalities faced triggered renewed calls for the change in its legal status.

In 2017 VI Convocation was formed by 24 delegates, 2 from each of Beli Manastir, Borovo, Markušica, Trpinja, Negoslavaci, Šodolovaci, Jagodnjak and Erdut and 1 from each of Stari Jankovci, Nijemci, Darda, Kneževi Vinogradi, Popovac and Tompojevci.

[52][53] Eastern Slavonia, as the area of daily activity of the Joint Council of Municipalities, is characterized by the existence of the regular elementary and secondary school education in minority languages including in Serbian.

Council President Dragan Crnogorac stated: From this important date (i.e. the date of the establishment), Joint Council of Municipalities, as an internationally recognised institution in Croatia, works on preserving of rights and interests of the Serbs, their cultural and educational autonomy, Serbian traditions, customs, language, and the Cyrillic alphabet, but also works on reconstruction, development, and improvement of the entire life of all citizens and because of this it is respected and stable partner of the government and of all entities that are committed to these values.