http://en.wikipedia.org/wiki/History_of_atheism
Although the term atheism originated in the 16th century, based on Ancient Greek godless, denying the gods, ungodly"[1] and open admission to positive atheism in modern times was not made earlier than in the late 18th century, atheistic ideas and beliefs, as well as their political influence, have a more expansive history.
The spontaneous proposition that there may be no gods after all is likely as old as theism itself (and the proposition that there may be no God as old as the beginnings of monotheism or henotheism). Philosophical atheist thought appears from the 6th or 5th century BCE, both in Europe and in Asia.
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Atheism in the 20th century found recognition in a wide variety of other, broader philosophies, such as existentialism, objectivism, secular humanism, nihilism, logical positivism, Marxism, feminism,[19] and the general scientific and rationalist movement. Neopositivism and analytical philosophy discarded classical rationalism and metaphysics in favor of strict empiricism and epistemological nominalism. Proponents such as Bertrand Russell emphatically rejected belief in God. In his early work, Ludwig Wittgenstein attempted to separate metaphysical and supernatural language from rational discourse.
A. J. Ayer asserted the unverifiability and meaninglessness of religious statements, citing his adherence to the empirical sciences. The structuralism of Lévi-Strauss sourced religious language to the human subconscious, denying its transcendental meaning. J. N. Findlay and J. J. C. Smart argued that the existence of God is not logically necessary. Naturalists and materialists such as John Dewey considered the natural world to be the basis of everything, denying the existence of God or immortality.[20][21]
The 20th century also saw the political advancement of atheism, spurred on by interpretation of the works of Marx and Engels. State support of atheism and opposition to organized religion was made policy in all communist states, including the People's Republic of China[22] and the former Soviet Union. In theory and in practice these states were secular. The justifications given for the social and political sidelining of religious organizations addressed, on one hand, the "irrationality" of religious belief, and on the other the "parasitical" nature of the relationship between the church and the population. Churches were sometimes tolerated, but subject to strict control - church officials had to be vetted by the state, while attendance of church functions could endanger one's career. Very often, the state's opposition to religion took more violent forms; Aleksandr Solzhenitsyn documents widespread persecution, imprisonments and torture of believers, in his seminal work The Gulag Archipelago. Consequently, religious organizations, such as the Catholic Church, were among the most stringent opponents of communist regimes. In some cases, the initial strict measures of control and opposition to religious activity were gradually relaxed in communist states. On the other hand, Albania under Enver Hoxha became, in 1967, the first (and to date only) formally declared atheist state.[23] Hoxha went far beyond what most other countries had attempted and completely prohibited religious observance, systematically repressing and persecuting adherents. The right to religious practice was restored in 1991.
In India, E. V. Ramasami Naicker (Periyar), a prominent atheist leader, fought against Hinduism and the Brahmins for discriminating and dividing people in the name of caste and religion.[24] This was highlighted in 1956 when he made the Hindu god Rama wear a garland made of slippers and made antitheistic statements.[25]
During the Cold War, the United States often characterized its opponents as "Godless Communists,"[26] which tended to reinforce the view that atheists were unreliable and unpatriotic. Against this background, the words "under God" were inserted into the pledge of allegiance in 1954,[27] and the national motto was changed from E Pluribus Unum to In God We Trust in 1956.
The early 21st century has continued to see secularism and atheism promoted in the Western world. This has been assisted by the Brights movement, as well as a plethora of accessible antitheist and secularist literature.[28] Authors of such books have included: Sam Harris, David Mills, Daniel Dennett, Ibn Warraq, Ayaan Hirsi Ali, Richard Dawkins, Christopher Hitchens, Victor J. Stenger, and Anthony C. Grayling. Currently among 16-29 year olds in the USA, atheism is rising at higher levels than ever before recorded
Thanks for the history lesson.