Plato, in his dialogue of “Critias”, writes first about the war between Atlanteans - Athenians, and then is referred to the origin of the Atlanteans as follows:
..."At the sharing of the known then regions of earth by the twelve gods, Atlantis was given to Poseidon because it was surrounded by sea. Poseidon chose a very beautiful valley of Atlantis to dwell. There lived Evenor with his wife Leucippe and their daughter Cleito.
When Poseidon saw beautiful Cleito fell in love with her and wanted to become his wife and queen of the island. And it happened. He chose a nice hill, where people built for him a shelter. It was surrounded by earth and water successive rings forming an inaccessible retreat. These zones of earth and sea, one around the other, were so perfect “as if he rounded them with a lathe”.
"In that place there were two springs spouted warm and cold water from the same opening.
Poseidon and Cleito gave birth to five couples of twin sons. For this reason, Poseidon pided the island into ten districts and crowned them all kings. He assigned to his first son, Atlas, the central area, where his palace was, and pronounced him the 'King of the kings' ”.
"...Atlantis was named after by Atlas, son of god and king of this island. His brothers that reigned in other areas of this big island were Gadeirus (Eumelous in Greek), Ampheres, Evaemon, Mneseus, Autochthon, Elasippus, Mestor, Azaes and Diaprepes.
Atlas had many offspring, that have been honored and retained the reign and unity of Atlantis for generations. King of the central area became every first son and successively granted the reign to his first son. Peace was due to the oath of the kings: “...never will one level his gun towards the other...”
This island was considered to be sacred, protected by the Sun, since he had taken it under his wings and everything was nice and wonderful...
...and the dialogue of “Critias” by Plato continues with the glorious technical works created by the Atlanteans and the administration of their nation.