Marxism and religion

^{The founder and primary theorist of Marxism, the nineteenth century German sociologist Karl Marx, had an ambivalent attitude to religion, viewing it primarily as "the opium of the people" that had been used by the ruling classes to give the working classes false hope for millennia, while at the same time recognizing it as a form of protest by the working classes against their poor economic conditions. In the end, Marx rejects religion.
In the Marxist-Leninist interpretation of Marxist theory, developed primarily by Russian revolutionary Vladimir Lenin, religion is seen as negative to human development, and socialist states that follow a Marxist-Leninist variant are atheistic and explicitly antireligious. Due to this, a number of avowedly Marxist governments in the twentieth century, such as the Soviet Union and the People's Republic of China, implemented rules introducing state atheism. However, several religious communist groups exist, and Christian communism was important in the early development of communism.}