20th century

== Religion ==
{{see also|List of 20th-century religious leaders}}
* 1900s – A number of related [[Pentecostalism#Early revivals: 1900–1929|revival movements]] mark the start of [[Pentecostalism]].
* 1904 – [[Aleister Crowley]] dictates ''[[The Book of the Law]]'', the foundational text of [[Thelema]].
* 1922 – The [[Soviet Union]] establishes a doctrine of [[state atheism#Soviet Union|state atheism]].
* 1924 – [[Mustafa Kemal Atatürk|Mustafa Kemal Pasha]] abolishes the Islamic [[Caliphate]], in favor of [[secularism]]. This marks the last widely recognized Muslim Caliphate.
* 1930 – [[Wallace Fard Muhammad]] founds the [[Nation of Islam]]. The [[Lambeth Conference#Seventh: 1930|Seventh Lambeth Conference]] allows for the possibility of [[Christian views on birth control#Anglicanism|birth control within Anglicanism]], the first example of a modern Christian church supporting such a position.{{citation needed|date=August 2022}}
* 1940s – [[Wicca]] is formalized by [[Gerald Gardner]] and [[Doreen Valiente]].
* 1950s – [[Sayyid Qutb]] articulates [[Qutbism]], a violent variety of [[Islamism]] that would later become foundational to [[jihadist]] ideology. [[Maharishi Mahesh Yogi]] begins to teach [[Transcendental Meditation]].
* 1953 – [[L. Ron Hubbard]] founds the [[Church of Scientology]], which has a unique cosmology based on [[Space opera in Scientology|science fiction]] and his older system of [[Dianetics]].
* 1956 – [[B. R. Ambedkar]] launches the [[Dalit Buddhist movement]].
* 1960 – The [[charismatic movement]] starts within Anglicanism, quickly spreading to other Christian sects.
* 1962–65 – The [[Second Vatican Council]] is held, resulting in significant changes in the [[Catholic Church]].
* 1970s – [[New Age]] beliefs and practices are popularized.
* 1979 – In [[Shia Islam]], the [[Islamic Revolution]] establishes a [[Government of the Islamic Republic of Iran|theocratic state within Iran]].
* 1988 – [[Al-Qaeda]], a network of [[Islamic extremists]], is founded among Arab members of the [[Afghan mujahideen]]. It engages in a number of terror attacks throughout the 1990s, leading up to the [[September 11 attacks]] in 2001.
* 1999 – [[Falun Gong]], a Chinese [[new religious movement]] dating to the early 1990s, begins to be [[Persecution of Falun Gong|persecuted]] by the Chinese government.