The destruction of Atlantis has been posited as having for its prototype the catastrophic eruption of the island of Santorini (Thera, modern Thira), previously regarded as having led to the end of the Minoan civilisation centred upon Crete. There are, however, a number of serious difficulties in maintaining this notion. Dendrochronology and radiocarbon dating evidence suggest that it occurred in around 1628 BC, whilst Egyptological evidence suggests that the decline of Crete as a major power occurred during the 18th dynasty at some point around 1450 BC, based to some extent on the chronology of the use of the term Keftiu, especially in relation to the weakening of Minoan society by the eruption as a possible trigger for incursions onto the island by mainland Greeks.
One of the major issues with the "Minoan Atlantis" hypothesis is that surviving Greek sources betray absolutely no knowledge of the conflagration. Herodotus mentions the settlement of Thera by Theras, a prince from the line of Cadmus at Thebes who threw his lot in with the invading Heraclids [4.147]. According to Herodotus, the island, which was formerly known as Calliste, had been home to a Phoenician colony descended from a certain Membliarus for eight generations.
The name Calliste came from a daughter of Triton who was transported into the Aegean from Lake Tritonis by the Argonaut Euphemus in the form of a clod of earth which, being washed overboard, became the island. Pindar knows the tale of the clod but it is left to Apollonius of Rhodes to connect it with the island of Calliste, which Euphemus "threw [...] into the depths of the sea, and there grew up from it an island called Calliste, the sacred Nurse of his descendants" [4.1734-1764: 4.1551-1561 describes how Triton, in the guise of Eurypylus son of Poseidon, gave it to them]. Taken together, there appears to be little room for the Santorini eruption in Greek historiography.
The notion of a "clod" (βῶλος) of earth thrown into the sea and growing into an island could be interpreted as redolent of a newly formed volcanic island - and, indeed, this has been a factor at Thera. Ian Thornton writes: -
Poseidonius recorded that an island, Hiera, rose up 'as if on springs' from the submerged caldera of Thera in 197 BC (Kraft 1991). This activity, which was both explosive and effusive (i.e. producing lava flows), quickly built up a largely pyroclastic cone known as Iera or Hiera. According to Aurelius Victor in Historia Romana, nearly two and a half centuries later, after Iera had disappeared, in AD 46 and 47, volcanic activity about 3 km south-west of Iera's position formed an island, Thia, about 1 km long and 500 m wide.
Though all of the islands Thornton describes appeared after Plato and Apollonius's floruit, it is not difficult to imagine the process occurring earlier too, though there is no evidence. Additionally, Calliste is identified with Thera, an island large enough to support a population and, as such, any suggestion that it was an ephemeral volcanic cone is highly unlikely. As such, it is difficult to state with certainty that Plato knew anything at all about the Bronze Age eruption of Santorini.
Additionally, the effects of the cataclysm on Minoan civilisation, whilst considerable, were not necessarily terminal. S.L. Budin has this to say: -
On the whole, the First Palace period was a productive time for the Minoans. Surplus, specialization, and organization mark this era, as do extensions outward into the broader world of the eastern Mediterranean. But, there was one inherent flaw in this almost ideal Minoan society - Crete is located very close to Thera, and Thera is volcanic. A volcano on Thera experienced a massive eruption in approximately 1640 B.C.E., taking much of Thera with it and causing considerable real estate damage on Crete. But the Minoans emerged from the literal ashes of their Middle Bronze Age society to create an even more glorious Late Bronze Age society. The 200 years following the eruption of Thera mark the apex of Minoan civilization.
Thucydides does mention Crete as a significant sea power under Minos' rule, crediting Minos as "the first person known to us by tradition as having established a navy" [1.1.4], with which he rid the Aegean of pirates and settled the Cyclades, facilitating communication [1.1.8] and the economic growth of his kingdom. Interestingly, Thucydides' pirates included Phoenicians, besides Carians (the historical Carians were a people of southwestern Asia Minor, whose territory included regions close to Herodotus' birthplace Halicarnassus).
Minos - who, as a son of Zeus, can hardly be described as one whose "portion of divinity [...] was now becoming faint and weak through being ofttimes blended with a large measure of mortality" [Crit. 121a] - was also well-regarded by Plato, for whom he was a significant lawgiver and, post-mortem, is found in his familiar guise as a judge of the dead, with Plato making him arbiter among the three judges, holding a casting vote on the fates of the souls of the deceased [Gorgias 524a]. As the story of the Athenian hero Theseus makes Minos an arrogant villain, the negative Athenian perspective of Minos was often in marked contrast with his reputation throughout the rest of Greece and neither Thucydides nor Plato appear to regard this negative portrayal as particularly important when emending Minos' achievements.
It would, perhaps be easier making a case for an indirect transmission for the account of the Santorini disaster via Egypt. Egyptian records name a people they term Keftiu, who were juxtaposed with the "western land" in a "Hymn of Victory" from the reign of Thutmose III [Ancient Records 2.659]. The majority of references to the Keftiu appear in and around the time of Thutmose III, who is usually placed in the 15th century BC.
Earlier records of contact between Crete and the Near East exist: the Mari archives contain records which give a place name Kap-ta-ra and Hyksos-period palace decoration from Avaris appear to be Minoan in origin, leading to suggestions of a Minoan presence on the site during the period. Minoan wall-paintings have also been found dating to the time of Thutmose III and his successor Amenhotep II.
Unfortunately, no extant records remain which indicate a violent end to the Minoan civilisation within Egypt: the Keftiu simply disappear from history. Additionally, the evidence suggesting that the major phase of the Santorini conflagration took place earlier than previously assumed decouples this event from the terminal period of Minoan grandeur, thus suggesting that the Minoans survived the cataclysm - indeed thrived in its aftermath. With this in mind, the connection between the Keftiu (if the assumption that they were the Minoan Cretans is correct) and Atlantis must be rejected.
Solon's initial speech to the Egyptians, which caused them such humour [Tim. 22ab], and which led to the priest's revelations about Athens' glorious past, reminds one of Herodotus' statement about the Egyptian response to Hecataeus and himself giving their genealogies [2.143b]. The 9,000 years is thus not especially relevant other than that it is a greater span of time than the 8,000 years separating the dawn of Egyptian civilisation from Solon's meeting with the priest. Plato's motives for providing such an early date for his Athens-Atlantis war are dealt with elsewhere. This section covers attempts to interpret the 9,000 years as something other than the plain statement in the text.
These interpretations mainly take the form of an identification between the Sea Peoples who ravaged Egypt and the Middle East at the end of the Bronze Age or the supposed catastrophic end of Minoan civilisation with Plato's Atlantis, and generally posit that the 9,000 years is either an error for 900, or else represents a reference to "lunar years" (months).
However, this is invalidated by Plato: his sole purpose in dating ancient Athens and Atlantis to such a remote time was that they both arose before civilisation appeared in Egypt (selon Plato, 1,000 years thereafter). Atlantis, therefore, can be found neither on Crete nor Santorini. It is surely impossible to arbitrarily reduce Plato's 9,000 years without putting forth a similar reduction to the 8,000 years of Egyptian - at the very least Saïte - history [Tim. 23de]. Either to maintain the 9,000 years as indisputable truth or to suggest a reduction based upon the figure smacks of cherry-picking evidence.
Similarly, proponents of the Minoan hypothesis propose a reinterpretation of portions of the text, but the invocation of Atlas and Gadeirus, both names associated with far-western locales, among the sons of Poseidon mitigates against the notion that μείζων (Tim. 24e; or μείζω - Crit. 108e), indicating "larger than," is an error for μέσος/μέσον, which would render the relevant passages "in the middle of" and vaguely connect Atlantis to Crete or Thira.
Anyhow, the question of the age of Atlantis and Athens is moot: Egyptian civilisation entered its dynastic era shortly before 3000 BC, with evidence of settlement at Athens dating to the Middle Neolithic in the preceding millennia.
Lycurgus was said to have "fixed the number of Spartan citizens at 9,000, each with a plot of land," a tradition related by the much later author Plutarch [Life of Lycurgus 8.3], which is perhaps a prototype of Plato's description of the allotment of the plain of Atlantis [Crit. 118d-119a]. It is also, however, quite probable that this tradition specifying 9,000 allotments postdates Plato as it is not mentioned by writers such as Herodotus, Xenophon or Aristotle.
9,000 is also a significant figure in Athenian history: during the 1st century BC, Cornelius Nepos, in his biography of Miltiades , suggested that the Athenian commander had 9,000 Athenian hoplites in his forces which defeated the Persians at Marathon.