But I have been able to research that the Macedon Phillip inherited was quite tiny by comparison to what later became called Macedonia. The original Macedonians did speak a dialect of Greek. Macedonia expanded under Phillip and Alexander, and Macedonia expanded yet again during the Roman Empire.
Then, during the Byzantine period, much of the Western part got carved up by Bulgaria & Serbia, hence the Slavic speaking Macedonians. Yet when the Turks conquered the Balkans, the term "Macedonia" pretty much fell into disuse.
In the late 19th and early 20th century, the retreat of the Turks, the Balkan Wars and the population exchange of Greeks in Turkey produced a massive migration and population exchange in Greater Macedonia. The Slavic-speaking Macedonians for the most part went North into Bulgarian Macedonia and NW into what became the Yugoslavian Macedonia, and a substantial number of Greeks coming from Turkey moved into Greek Macedonia. Some of Greater Macedonia even wound up as part of Albania
Here are some maps. The 1st one shows Macedonia (at its largest) crossing the borders of several countries:
And here's one that shows the Macedon of Phillip, in yellow and it's expansion crossing borders.
