Atlantis is a fictional island first described in the works of the Greek philosopher Plato, specifically within his dialogues Timaeus and Critias. In these texts, it serves as an allegory regarding the hubris of nations. Plato depicted Atlantis as a powerful naval empire from the west that conquered significant portions of Europe and Libya.
The narrative describes Atlantis losing divine favor following a failed military campaign against a fictionalized version of Athens. According to the account, the island subsequently submerged into the Atlantic Ocean. By contrasting the maritime power of Atlantis with the land-based Achaemenid Empire, Plato intended to highlight the superiority of his own ideal state as represented by the victorious Athens.