The origin of the geographical terminology is arguable. A similar term was used in 1944 to describe a unit fighting in the Second World War called the "First Aegean Macedonian Brigade" , although there is no evidence that this is the first usage of the term "Aegean Macedonia".
During the Greek Civil War, in 1947 the Greek Ministry of Press and Information published a book, I Enandion tis Ellados Epivoulis ("Designs on Greece"), namely of documents and speeches on the ongoing Macedonian issue, many translations from Yugoslav officials. It reports Josip Broz Tito using the term 'Aegean Macedonia' on the 11th October, 1945 in the build up to the Greek Civil War; the original document is archived in ‘GFM A/24581/G2/1945’. For Athens in 1947, the “new term, Aegean Macedonia”, (also “Pirin Macedonia”), was introduced by Yugoslavs. Contextually, this observation indicates this was part of the Yugoslav offensive against Greece, laying claim to Greek Macedonia, but Athens does not seem to take issue with the term itself . The 1945 date concurs with Bulgarian sources.
Tito's war time representative to Macedonia, General Tempo (Svetozar Vukmanovic), is credited with promoting the usage of the new regional names of the Macedonian region for irredentist purposes. Indeed, Tsola Dragoiocheva, in her Memoirs, 'Pobadata', Sofia 1979, writes that, "Under pressure from Tempo, the Yugoslav Macedonian Headquarters issued a Manifesto in October 1943, for the slogan about a 'united Macedonia', which began to crop up in Communist Party of Yugoslavia documents. Hitherto, the Yugolsav party leadership only had designs on Vardar Macedonia." Tempo himself wrote  that, "The slogan about a united Macedonia first appeared in the Manifesto of the Headquarters of the National Liberation Army of Macedonia, at the beginning of October 1943. There had been no mention of it earlier in any document either in Yugoslavia or in Macedonia". Tempo also attacked the Greek Communist Party (KKE) because it, "only recognises the Macedonian people of Aegean Macedonia a right to equality in the framework of the Greek State" . The ideological context was always 'anti bourgeois-democratic parties' and in line with communist ideology.
In 1946, the Belgrade newspaper Borba, (August 26, 1946) published an article under the title "Aegean Macedonia", it was also published in Skopje’s Nova Makedonija with a map of Yugoslav territorial claims against Greece. A month later, on September 22, the Premier of the People's Republic of Macedonia, Dimitar Vlahov [speech in Nova Makedonija, on September 26, 1946] announced, "We openly declare that Greece has no rights whatsoever over Aegean Macedonia...". Vlahov then went on to publish, "The Problems of Aegean Macedonia", Belgrade, June 1947.
By 1950, the term 'Aegean Macedonians' had been officially adopted by the Slav Macedonian political separatists in Skopje  who began publishing their own organ, ‘The Voice of the Aegeans’; it is later found amongst militant diaspora communities. .
The Slav Macedonians in Greece seemed relieved to be acknowledged as Slavomacedonians. A native of the region, former exile and local historian, Pavlos Koufis, says in Laografika Florinas kai Kastorias (Folklore of Florina and Kastoria) , that,
“[During its Panhellenic Meeting in September 1942, the KKE mentioned that it recognises the equality of the ethnic minorities in Greece] the KKE recognised that the Slavophone population was ethnic minority of Slavomacedonians]. This was a term, which the inhabitants of the region accepted with relief. [Because] Slavomacedonians = Slavs+Macedoninas. The first section of the term determined their origin and classified them in the great family of the Slav peoples.”
The name "Aegean Macedonia" is considered by the Greeks as ambiguous and offensive. On one hand it contains a reference to a geographical area they consider historically Greek (the Aegean), but, as expressed above, there is also the experience that it is used by irredentist organizations in FYROM and beyond who support a United Macedonia, contrary to the desires of the people living in the area.
Writing in 1953, Lazar Mojsov seems surprised that the Greeks find the term "Aegean Macedonia" insulting, and uses it frequently, noting that "...Politis (former Greek minister of external affairs) didn't miss the opportunity to attack even the very term "Aegean Macedonia", stating that it was "coined by the communist propagandists" .
The term is currently used by some scholars, mostly contextualised, along with the sister terms Vardar Macedonia (describing the part of Macedonia in which the FYROM inhabits) and Pirin Macedonia (describing the part of Macedonia in which the Blagoevgrad province of Bulgaria inhabits). The term is used more frequently by Slav Macedonians and can have irredentist connotations, in relation to the concept of United Macedonia.
- "The Macedonian Conflict: Ethnic Nationalism in a Transnational World", Loring M. Danforth, p. 37
- Autonomist Movements of the Slavophones in 1944, Spyridon Sfetas, Balkan Studies, 36/2 (1995), 297-317.
- Struggle for the Balkans,London: Merlin 1980
- How and why the people's Liberation struggle of Greece met with defeat (O narodnou revolucijiu u Grckoj), Manchester: Merlin Press, 1985, original 1949
- International Organization, Vol. 1, No. 3, (Sep., 1947), pp.494-508. Appointed under the Security Council resolution of December 19, 1946, the "Commission of Investigation Concerning Greek Frontier Incidents" on May 27, 1947 submitted a report, to the Security Council.The general conclusion of the UN Commission as about Macedonia issue, was that Yugoslav and Bulgarian Governments themselves revived and promoted a separatist movement among the Slav minorities in Macedonia.In making this finding, the Commission pointed out that some 20,000 Greek citizens had fled to Yugoslavia and some 5,000 to Bulgaria — most of them Slavs — and that the treatment of this group by Greek officials had "provided fertile breeding ground for separatist movements." In Yugoslavia, Macedonian separatism was the special goal of an organization called the NOF (National Labor Front) which had its headquarters in Skopje and Monastirion(Bitola).
- These separatists were born in Greece and in 1949 fled to Tito’s Communist ‘Socialist Republic of Macedonia’ and who years before (during Greece’s occupation by the Axis in 1941-1944) had openly expressed pro-Bulgarian sentiments and affiliations and enthusiastically collaborated with the Bulgarian allies of the Nazis, and the infamous Bulgarian Ohrana Police Battalions –operating in Both Macedonia and Thrace. Those very people (especially in Western Macedonia) in the aftermath of the Axis (including Bulgarian) defeat in 1944 and in order to avoid the dire consequences of their treason and collaboration decided, literally overnight, to make a drastic and highly opportunistic change of their political affiliations and national consciousness.
- Some of this material is quoted from, E. Kofos, Nationalism and Communism in Macedonia, Thessaloniki, Institute of Balkan Studies, 1964
- 'Laografika Florinas kai Kastorias', Athens, 1996, probably published by the author
- Лазо Мојсов, Околу прашањето на македонското национално малцинство во Грција, ИНИ, Скопје, 1954)