The first inhabitants of Egypt were the Pelasgians from Argos and, later, from other areas of Greece, who arrived there before the Cataclysm (9600 BC). One of the oldest cities founded near the beginning of the Nile Delta was Memphis, built by Epaphos, the "son" of Io (Greek Ιώ) from Argos, for his wife Memphis. Memphis is about 20 km south of Cairo.
According to Plato, Sais - a city in the Delta - had been built by the Athenians in 8600 BC, a thousand years after the war with the Atlantians (9600 BC). Heliopolis (Cairo) had been built by Aktis (= Ray), a "son" of Helios (= Sun - Diodorus 4,57). Diodorus informs us that the Egyptian priests of his time had explained to him that the god Helios had ruled Egypt 23,000 years before Alexander the Great. In my books I have shown for the first time (since 1986) that Helios was a Pelasgian king-god from Peloponnesus. The Greek state of Elia in western Peloponnesus was named after him. Heliopolis is also mentioned in Exodus (A' 11) "...καί 'Ων, ή έστιν Ηλιούπολις" (...and On, that is Heliopolis).
Epaphos married Memphis and became the father of Libya. Her name was given to the country around Egypt, that is to the continent Africa. Then Libya became the mother of Belos and Agenor from Poseidon. Belos - a very important king-god of Egypt - was the father of Aegyptos and Danaos, and Agenor (who went to Phoenike) the father of Kadmos, Phoenics, Kilics and Europe. The country in the Nile valley was named Aegyptos after the "son" of Belos. (* The sons and daughters mentioned in Greek mythology are descentants).
In those days - before and after the Cataclysm - the river was called Aegyptos (Homer). The Cretans, who built many cities in this area, called the country Aeria (= Airy) because Aeria was an older name for Crete. Around 6000 BC some other people of Semitic origin arrived in Egypt from Arabia and the population changed later.
Aeshylos Prometheus 570-590
Herodotos B' 59, 98, 156
Apollodoros B' 1
Plutarchos On Osiris and Isis
Pausanias B' 16.1, C' 18.3
Suda (in Ιώ)