Today's definition of the geographical region of Macedonia includes the present Greek administrative region of Macedonia as well as the whole of the Former Yugoslav Republic of Macedonia (FYROM). However, it also includes parts of Albania, Bulgaria, Serbia and small pieces of Kosovo.

Originally, the ancient kingdom of Macedonia — or Macedon — was a relatively small part of the present-day Greek province of Macedonia. It first expanded under King Perdiccas I, then widened to take in other areas, including the three-fingered peninsula of Halkidiki and parts near to the border with present-day Albania.

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Tiny kingdom achieves world domination

Neighboring areas like Thrace (which includes European Turkey) and Paeonia (the modern-day FYROM) became dependent territories of Macedonia. King Philip II went on to subdue the Greek mainland before his son Alexander the Great took the whole of Greece. Alexander would go on to conquer the First Persian Empire and extend his boundaries as far east as India.

Arguably, at this point, Macedonia's realms stretched as far as the Indus River and the Nile in Egypt. By the time Alexander was in power, though, Macedonia was very much "Hellenized" – or culturally Greek. As a result, the language, culture and genes that Alexander's empire carried eastward were Greek.

Roman expansion, then a shift east

After the fall of the Greek Empire, the Romans used the old name Macedonia for the province encompassing much of northern Greece and the area north of it, including much of the modern-day Former Yugoslav Republic of Macedonia. The province, at least for a time, stretched westward to the Adriatic and south into central Greece.

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With the breakup of the Roman Empire into East and West, this region was overrun by the Slavic invasions. An entirely new province far to the east, in modern-day Turkey, was named Macedonia by the Byzantine Empress Irene of Athens. The entire region subsequently fell to the Ottoman Empire.

Ottoman root of modern boundaries

The geographic region known as Macedonia today equates to the part of the Ottoman Empire known as Ottoman Vardar Macedonia. It included Greek and Slavic areas and was split into three administrative units, but the concept of Macedonia persisted.  This remained the case for centuries and so this idea — of what Macedonia is — has stuck.

An "awakening” nationalism among ethnic Slavs in the region who identified as Macedonian took place in the late 19th century. The emergence of this Macedonian identity among the Slavs living in the region is still seen as a relatively new one.

As the Ottoman Empire crumbled, the Slavic or western Bulgarian part of Vardar Macedonia eventually became a part of the Kingdom of Yugoslavia known as Southern Serbia. The area was later called Vardar Banovina (a banovina being a province of the Yugoslav kingdom). The name Macedonia was prohibited.

Macedonia's re-emergence, Greek consternation

After occupation in World War II, the old banovina was pared down and it became the People's Republic of Macedonia — subsequently the Socialist Republic of Macedonia. Yugoslav authorities now sought to promote Macedonian nationalism, and the Macedonian language, which had been thought of until then as a western Bulgarian dialect, was codified.

The fact that this Macedonian language was Slavic did not go down too well with the Greeks.

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With the breakup of Yugoslavia, things got worse. Athens became anxious about a movement within the new Republic of Macedonia to appropriate the legacy of Alexander the Great. Specifically, it feared the concept of a United Macedonia that could include Alexander's heartland in Greece itself.

The Greeks also accused the new republic of hijacking symbols such as the Vergina Sun – a symbol of ancient Macedonia – which feature on the new country's first flag. In 1995, the young state was forced to change its flag to feature a rayed sun instead.

It's the name Macedonia that rankles most with Greece, though. The new country was admitted to the United Nations only on condition that it used the provisional description FYROM. Athens insists that if the FYROM must use the name Macedonia at all, it should be preceded by a geographic qualifier such as Northern or Upper Macedonia.

As if that weren’t complicated enough, there's another meaning of the word Macedonia. In Greece and many Latin language-speaking countries, it's also a fruit salad. The name is thought to have been popularized at the end of the 18th century, referring to either the ethnic diversity of Alexander's vast empire, or the ethnic mix of Ottoman Macedonia.