By the late eighteenth century, however, a second form of millennialism was developing, unconnected to religious concepts. This consisted of secular visions of a perfect future — ideas propelled by faith in transcendent but not conventionally religious forces. These forces were sometimes identified with reason, and sometimes with science or history. By the late nineteenth century, secular millenarian visions had become closely linked with political ideologies, especially those that grew out of ideas about nationality, class, and race. Hence the twentieth century was both dominated and scarred by Marxism, Nazism, and a host of nationalisms, all of which promised a millennial consummation to some group judged to be particularly worthy. Like earlier religious millenarians, these secular ideologists linked the end-times with a great battle between the forces of good and evil — not a literal, biblical Armageddon, but a struggle of comparably cosmic importance.
– A Culture of Conspiracy: Apocalyptic Visions in Contemporary America (2013), p. 16
“New Age” is clearly the most recent constituent, and its very recency poses definitional problems. For present purposes, I employ J. Gordon Melton’s definition, which includes the following elements: mystical individual transformation; an awareness of new, nonmaterial realities; “the imposition of [a] personal vision onto society”; and belief in universally pervasive but invisible forms of energy.
– Ibid., p. 19