What is the history of apocalyptic mythologies

The fear of the unknown makes a large part of many mythologies for cultures around the world in ancient and even modern times. The end of the world, or the apocalypse as commonly known, is a genre of mythologies that reflects our deepest fears not only for ourselves but usually our society and culture. This could be, at times, based on some reality or stories of crises for a given culture or society, while at other times it represents a warning that society should heed or even change its ways before it is too late.