The Bibliotheca historica (1st century BCE) of Diodorus Siculus, Book XII, Chapter 34, states: "And while these events [the Battle of Potidaea] were taking place, the Athenians founded in the Propontis a city which was given the name of Astacus". Siculus' annalistic narrative allows the founding to be dated to the year 435 BCE.[3]
The About Hericlea (Ancient Greek: Περί Ηρακλείας, romanized: Peri Herakleias; 1st century CE) of Memnon of Heraclea, which has only been partially preserved through the Excerpta of Photius, states: "Astacus was founded by settlers from Megara at the beginning of the 17th Olympiad and was named as instructed by an oracle after one of the so-called indigenous Sparti (the descendants of the Theban Sparti), a noble and high-minded man called Astacus".[8] The 17th-century Ussher chronology dated the founding as 712/11 BCE, the first year of the 17th Olympiad.[9]
Strabo wrote that some time after Astacus was 'a colony of Megarians and Athenians', it was 'of Doidalsos', whose identity is not specified.[4] Memnon does say that '[Astacus] achieved great glory and strength, when Dudalsos had the dominion of the Bithynians', but does not say whether the city was controlled by those Bithynians at the time, nor when this was.[8]
Strabo wrote that Lysimachus (r. 306 – 281 BCE) razed Astacus to the ground.[4]
Nicomedes I, son of Zipoetes, founded a new city to replace Astacus across from its former location, which he named Nicomedia after himself, bringing some of the Astacan cults to the new site. Nicomedia remained the capital of Bithynia, and became one of the great cities of the Roman east; the Emperor Diocletian made it his usual capital.
^ abcdStrabo (1903). "12.2". Geographica. Translated by W. Falconer. Ἦν δ' ἐν αὐτῷ τῷ κόλπῳ καὶ Ἀστακὸς πόλις, Μεγαρέων κτίσμα καὶ Ἀθηναίων καὶ μετὰ ταῦτα Δοιδαλσοῦ, ἀφ' ἧς καὶ ὁ κόλπος ὠνομάσθη: κατεσκάφη δ' ὑπὸ Λυσιμάχου: τοὺς δ' οἰκήτορας μετήγαγεν εἰς Νικομήδειαν ὁ κτίσας αὐτήν. (And on the gulf itself there was also a city Astacus, founded [sic] by [sic] the Megarians and Athenians and afterwards by [sic] Doedalsus; and it was after the city Astacus that the gulf was named. It was razed to the ground by Lysimachus, and its inhabitants were transferred to Nicomedeia by the founder of the latter.)