Dorians
The Dorians were the members of a major division of the Ancient Greeks. Sparta is the most known city of Doric origin. The Dorian invasion of and/or migration to Greece, and relations to the Bronze Age collapse and the Sea Peoples, have caused much speculation.
History
The Dorians were one of three populations into which the ancient Greeks divided themselves. Herodotus gave the earliest historical expression of a three-fold division: "... those who dwell in our land are called Ionians, Aeolians and Dorians." General names inherited from earlier times were considered to be in one of these three groups, from the earliest literature; for example, the Achaeans (also known as Danaans, Δαναοί, and Argives, Ἀργεῖοι) were primarily Ionians and Aeolians.
The three groups are seldom described by abstract concepts in the ancient sources. The Dorians are almost always simply referenced as just "the Dorians," as they are in the earliest literary mention of them in the Odyssey, where they are already in Crete. Herodotus does use the abstract ethnos with regard to them, the Greek word from which English ethnic comes, which appears in the modern concept of ethnic group.
The meaning of the abstract in ancient Greek depends on the context. It is often translated as "tribe", "race" or "people." The Dorians do not fit any of those English categories. No racial distinctions are ever portrayed; they are Hellenes along with the other two groups, nor were they a tribe. They were diverse in way of life and social organization, varying from the urbane city of Corinth known for its ornate style in art and architecture to the military state of Sparta. The identity included hill tribes as well, but they were not united into a single tribe.
And yet all the Hellenes knew what localities were Dorian and what not. Dorian states at war could more likely than not (but not always) count on the assistance of other Dorian states. Dorians were distinguished by the Doric Greek dialect and by characteristic social and historical traditions. Traditional accounts place their origins in the north, north-eastern mountainous regions of Greece, ancient Macedonia and Epirus, whence obscure circumstances brought them south into the Peloponnese, to certain Aegean islands, parts of the coast of Asia Minor and Magna Graecia and Crete. Mythology gave them an eponymous founder, Dorus son of Hellen, the mythological patriarch of the Hellenes.
In the fifth century BC, Dorians and Ionians were the two most politically important Greek ethne, whose ultimate clash resulted in the Peloponnesian War. The degree to which fifth-century Hellenes self-identified as "Ionian" or "Dorian" has itself been disputed. The fifth- and fourth-century literary tradition through which moderns view these ethnic identifications was profoundly influenced by the social politics of the time. Also, according to E.N. Tigerstedt, nineteenth-century European admirers of virtues they considered "Dorian" identified themselves as "Laconophile" and found responsive parallels in the culture of their day as well; their biases contribute to the traditional modern interpretation of "Dorians".
When allowances have been made for the sometimes multiple lenses through which history is viewed, modern readers have also to align the literary sources with the archaeological record, if this is possible.