Postchristianity is the loss of the primacy of the Christian worldview in political affairs, especially in the Global North where Christianity had previously flourished, in favor of alternative worldviews such as secularism or nationalism. It includes personal world views, ideologies, religious movements or societies that are no longer rooted in the language and assumptions of Christianity, at least explicitly, although they had previously been in an environment of ubiquitous Christianity (i.e. Christendom).
Other scholars have disputed the global decline of Christianity, and instead hypothesized of an evolution of Christianity which allows it to not only survive, but actively expand its influence in contemporary societies.
Historically, the majority of Christians have lived in Western, White nations, often conceptualized as "European Christian" civilization. Many theorists argue that Christianity was an important ideological branch of Western imperialism and tied to the history and success of colonialism. As a result, the loss of Christian influence in the West and the development of postcolonialism have led to beliefs of inevitable global decline of Christianity.
A postchristian world is one in which Christianity is no longer the dominant civil religion but has gradually assumed values, culture, and worldviews that are not necessarily Christian (and also may not necessarily reflect any world religion's standpoint or may represent a combination of either several religions or none). Post-Christian tends to refer to the loss of Christianity's monopoly, if not its followers, in historically Christian societies. Postchristian societies can be found across the Global North - for example, though the 2005 Eurobarometer survey indicated that the majority of Europeans hold some form of belief in a higher power, fewer point explicitly to the Christian God.