United Macedonia (Macedonian: Обединета Македонија, romanized: Obedineta Makedonija), or Greater Macedonia (Macedonian: Голема Македонија, romanized: Golema Makedonija), is an irredentist concept among Macedonian nationalists that aims to unify the transnational region of Macedonia in Southeastern Europe (which they claim as their homeland and which they assert was unjustly divided under the Treaty of Bucharest in 1913) into a single state that would be dominated by ethnic Macedonians. The proposed capital of such a United Macedonia is the city of Thessaloniki (Solun in the Slavic languages), the capital of Greek Macedonia.

The roots of the concept can be traced back to the 1910 First Balkan Socialist Conference as a possible solution of the Macedonian Question. Georgi Dimitrov, a Bulgarian politician, wrote in 1915 that the creation of a "Macedonia, which was split into three parts, was to be reunited into a single state enjoying equal rights within the framework of the Balkan Democratic Federation".^{[1][non-primary source needed]} In 1924, the Communist International suggested that all Balkan communist parties adopt a platform of a "united Macedonia" but the suggestion was rejected by the Bulgarian and Greek communists.^[2] In 1934 the Comintern issued an official political document, in which for the first time, an authoritative international organization recognized the existence of a separate Macedonian people and a Macedonian language.

According to the Yugoslav communist Svetozar Vukmanović, the slogan about a united Macedonia appeared in the manifesto of the HQ of the National Liberation Army of Macedonia, at the beginning of October 1943.^[3] At that time Vukmanović was sent by Tito to macedonianize the Communist struggle in Macedonia, and to give it a new ethnic-Macedonian facade. One of his main achievements was that wartime pro-Bulgarian sentiments of the local communists to be receded into pro-Yugoslavism. As a result, the pro-Bulgarian Regional Committee of Communists in Macedonia was dissolved and replaced by a new Communist Party of Macedonia, as part of the Yugoslav Communist Party.^[4]

The Yugoslav communists recognized the separate Macedonian nationality to reduce the fears of the Macedonian Slavic population that they would continue the former Yugoslav policy of forced Serbianization. They did not support the view that the Macedonian Slavs are Bulgarians, because that meant in practice, the area should remain part of Bulgaria after the war.^[5] Afterwards the Yugoslav communists proclaimed as their aim the unification of Macedonia's three regions (Yugoslav, Greek and Bulgarian), thus attracting the Macedonian nationalists.

During the following operations of the National Liberation War of Macedonia the Macedonian Communist combatants developed aspirations over the geographic region of Macedonia that continued after 1944 during the Greek Civil War. The Bled agreement (1947) signed by the communist leaders Georgi Dimitrov and Josip Broz Tito also foresaw the unification of Yugoslav and Bulgarian Macedonia. It was also the first time that Bulgaria recognized ethnic Macedonians and the Macedonian language. After the Tito–Stalin split in 1948 and the death of Dimitrov in 1949, in the same year, the communists lost the Civil War in Greece. That put to an end the practical application of the concept.

Since 1989, Macedonian nationalists have called for a "United Macedonia", stating that "Solun (Thessaloniki) is ours" and "We fight for a United Macedonia".^[6][7][8] Several maps depicting "United Macedonia" as an independent country, stating irredentist claims of the Macedonian nationalists against both Greek and Bulgarian territory, circulated since the late 1980s and the beginning of the 1990s. In one of those maps all of Mount Olympus was incorporated in the territory of "United Macedonia".^[9] The Macedonian nationalists^[10] break down the region of Macedonia as follows:

• Vardar Macedonia (Вардарска Македонија) which includes:
  • the territory of North Macedonia;
  • Gora (Гора), small portions of southern Kosovo and eastern Albania
  • Prohor Pčinski (Прохор Пчински), southern Serbia; and
• Greek Macedonia (or "Aegean Macedonia", "Егејска Македонија"), northern Greece;
• Blagoevgrad Province (or "Pirin Macedonia", "Пиринска Македонија"), southwestern Bulgaria; and
• Mala Prespa and Golo Brdo (Мала Преспа и Голо Брдо), Albania.

Macedonian nationalists describe the above areas as the unliberated parts of Macedonia and they claim that the majority of the population in those territories are oppressed ethnic Macedonians. In the cases of Bulgaria and Albania, it is said that they are undercounted in the censuses (In Albania, there are officially 5,000 ethnic Macedonians, whereas Macedonian nationalists claim the figures are more like 120,000-350,000.^[11] In Bulgaria, there are officially 1,600 ethnic Macedonians, whereas Macedonian nationalists claim 200,000^[12]). In Greece, there is a Slavic-speaking minority with various self-identifications (Macedonian, Greek, Bulgarian), estimated by Ethnologue and the Greek Helsinki Monitor as being between 100,000-200,000 (according to the Greek Helsinki Monitor only an estimated 10,000-30,000 have an ethnic Macedonian national identity^[13]). The government of Macedonia, led by nationalist party VMRO-DPMNE, claimed^[when?] that there is an ethnic Macedonian minority numbering up to 750,000 in Bulgaria and 700,000 in Greece.^[14]

In its first resolution, VMRO-DPMNE, the nationalistic^{[15][16][17][18][19][20][21]} governing party at the time of the then-Republic of Macedonia, adopted the platform of a "United Macedonia",^[22] an act that has annoyed moderate Macedonian politicians and has also been regarded by Greece as an intolerable irredentist claim against Greek Macedonia.^[23] Before and just after independence, it was assumed in Greece that the idea of a united Macedonia was still state-sponsored.

During VMRO-DPMNE's rule, the United Macedonia concept was present in official sources in current North Macedonia,^[24][25] and was taught in schools through school textbooks and through other governmental publications.^[26][27]

• Autonomy for Macedonia and Adrianople regions
• Independent Macedonia
• Independent Macedonia (1944)
• Macedonia naming dispute
• Macedonia (terminology)
• Demographic history of Macedonia
• History of North Macedonia
• Titoism