Doric was spoken in a vast area, including northern Greece (Acarnania, Aetolia, Epirus, western and eastern Locris, Phocis, Doris, and possibly ancient Macedonia), most of the Peloponnese (Achaea, Elis, Messenia, Laconia, Argolid, Aegina, Corinthia, and Megara), the southern Aegean (Kythira, Milos, Thera, Crete, Karpathos, and Rhodes), as well as the colonies of some of those regions in Cyrene, Magna Graecia, the Black Sea, the Ionian Sea and the Adriatic Sea.

It was also spoken in the Greek sanctuaries of Dodona, Delphi, and Olympia, as well as at the four Panhellenic festivals; the Isthmian, Nemean, Pythian, and Olympic Games.

[5] The only living descendant of Doric is the Tsakonian language which is still spoken in Greece today;[6] though critically endangered, with only a few hundred – mostly elderly – fluent speakers left.

Southern dialects, in addition to numerous inscriptions, coins, and names, have also provided much more literary evidence through authors such as Alcman, Pindar, and Archimedes of Syracuse, among others, all of whom wrote in Doric.

There are also ancient dictionaries that have survived; notably the one by Hesychius of Alexandria, whose work preserved many dialectal words from throughout the Greek-speaking world.

Tsakonian, a descendant of Laconian Doric (Spartan), is still spoken on the southern Argolid coast of the Peloponnese, in the modern prefectures of Arcadia and Laconia.

Laconian was spoken by the population of Laconia in the southern Peloponnese and also by its colonies, Taras and Herakleia in Magna Graecia.

Many documents from the state of Sparta survive, whose citizens called themselves Lacedaemonians after the name of the valley in which they lived.

Argolic was spoken in the thickly settled northeast Peloponnese at, for example, Argos, Mycenae, Hermione, Troezen, Epidaurus, and as close to Athens as the island of Aegina.

As Mycenaean Greek had been spoken in this dialect region in the Bronze Age, it is clear that the Dorians overran it but were unable to take Attica.

Ample inscriptional material of a legal, political and religious content exists from at least the sixth century BC.

[14] Throughout the Northwest Doric area, most internal differences did not hinder mutual understanding, though Filos, citing Bubenik, notes that there were certain cases where a bit of accommodation may have been necessary.

Brian D. Joseph acknowledges the closeness of Macedonian to Greek (even contemplating to group them into a "Hellenic branch" of Indo-European), but retains that "[t]he slender evidence is open to different interpretations, so that no definitive answer is really possible".

[31] However, according to Hatzopoulos, B. Helly expanded and improved his own earlier suggestion and presented the hypothesis of a (North-)'Achaean' substratum extending as far north as the head of the Thermaic Gulf, which had a continuous relation, in prehistoric times both in Thessaly and Macedonia, with the Northwest Greek-speaking populations living on the other side of the Pindus mountain range, and contacts became cohabitation when the Argead Macedonians completed their wandering from Orestis to Lower Macedonia in the 7th c.

[31] According to this hypothesis, Hatzopoulos concludes that the Macedonian Greek dialect of the historical period, which is attested in inscriptions, is a sort of koine resulting from the interaction and the influences of various elements, the most important of which are the North-Achaean substratum, the Northwest Greek idiom of the Argead Macedonians, and the Thracian and Phrygian adstrata.

[32] It was spoken in Achaea in the northwestern Peloponnese, on the islands of Cephalonia and Zakynthos in the Ionian Sea, and in the Achaean colonies of Magna Graecia in Southern Italy (including Sybaris and Crotone).

[5] The Northwest Doric koine refers to a supraregional North-West common variety that emerged in the third and second centuries BC, and was used in the official texts of the Aetolian League.

[37] It was apparently based on the most general features of Northwest Doric, eschewing less common local traits.

[35][38] Its rise was driven by both linguistic and non-linguistic factors, with non-linguistic motivating factors including the spread of the rival Attic-Ionic koine after it was recruited by the Macedonian state for administration, and the political unification of a vast territories by the Aetolian League and the state of Epirus.