Atlantis (Ancient Greek: Ἀτλαντὶς νῆσος, romanized: Atlantìs nêsos, lit. 'island of Atlas') is a fictional island mentioned in Plato's works Timaeus and Critias as part of an allegory on the hubris of nations. Purposely creating a literary contrast with the Achaemenid Empire, the great land-based power that ruled the east (what the Greeks called Asia), Plato describes Atlantis as a naval empire from the west that had conquered most of Europe and Libya, but then loses divine favor after an ill-fated campaign against a fictionalized Athens and subsequently submerges into the Atlantic Ocean. By portraying the victorious Athens in the image of his ideal state from the Republic, Plato intended the Atlantis story to bear witness to the superiority of his concept of a state.
Despite its minor importance in Plato's work, the Atlantis story has had a considerable impact on literature. The allegorical aspect of Atlantis was taken up in utopian works of several Renaissance writers, such as Francis Bacon's New Atlantis and Thomas More's Utopia. On the other hand, nineteenth-century amateur scholars misinterpreted Plato's narrative as historical tradition, most famously Ignatius L. Donnelly in his Atlantis: The Antediluvian World. Plato's vague indications of the time of the events (more than 9,000 years before his time) and the alleged location of Atlantis ("beyond the Pillars of Hercules") gave rise to much pseudoscientific speculation. As a consequence, Atlantis has become a byword for any and all supposed advanced prehistoric lost civilizations and continues to inspire contemporary fiction, from comic books to films.