<P> In 2013, the AMC series The Walking Dead had the highest audience ratings in the United States for any show on broadcast or cable with an average of 5.6 million viewers in the 18 - to 49 - year - old demographic . </P> <P> Intimately tied to the concept of the modern zombie is the "zombie apocalypse"; the breakdown of society as a result of an initial zombie outbreak that spreads . This archetype has emerged as a prolific subgenre of apocalyptic fiction and has been portrayed in many zombie - related media after Night of the Living Dead . In a zombie apocalypse, a widespread (usually global) rise of zombies hostile to human life engages in a general assault on civilization . Victims of zombies may become zombies themselves . This causes the outbreak to become an exponentially growing crisis: the spreading phenomenon swamps normal military and law enforcement organizations, leading to the panicked collapse of civilized society until only isolated pockets of survivors remain, scavenging for food and supplies in a world reduced to a pre-industrial hostile wilderness . Possible causes for zombie behavior in a modern population can be attributed to viruses, bacteria or other phenomena that reduce the mental capacity of humans causing them to behave in a very primitive and destructive fashion . </P> <P> The usual subtext of the zombie apocalypse is that civilization is inherently vulnerable to the unexpected, and that most individuals if desperate enough cannot be relied on to comply with the author's ethos . The narrative of a zombie apocalypse carries strong connections to the turbulent social landscape of the United States in the 1960s, when Night of the Living Dead provided an indirect commentary on the dangers of conformity, a theme also explored in the novel The Body Snatchers (1954) and associated film Invasion of the Body Snatchers (1956). Many also feel that zombies allow people to deal with their own anxieties about the end of the world . One scholar concluded that "more than any other monster, zombies are fully and literally apocalyptic...they signal the end of the world as we have known it ." While zombie apocalypse scenarios are secular, they follow a religious pattern based on Christian ideas of an end - times war and messiah . </P> <P> Due to a large number of thematic films and video games, the idea of a zombie apocalypse has entered the mainstream, and many fans have begun making efforts to prepare for the hypothetical future zombie apocalypse . Such efforts include creating weapons and selling educational material informing people how to survive a zombie outbreak; while most of these are tongue - in - cheek and do not represent an authentic belief that a zombie apocalypse in the near future is likely, the Centers for Disease Control and Prevention (CDC) have used the fictional scenario to demonstrate survival and emergency - preparedness techniques that may be useful in a "real - world" setting . </P>

Who came up with the concept of zombies