The Great Leap Forward of the People's Republic of China (PRC) was an economic and social campaign of the Communist Party of China (CPC), reflected in planning decisions from 1958 to 1961, which aimed to use China's vast population to rapidly transform the country from an agrarian economy into a modern communist society through the process of rapid industrialization, and collectivization. Mao Zedong led the campaign based on the Theory of Productive Forces, and intensified it after being informed of the impending disaster from grain shortages. Chief changes in the lives of rural Chinese included the introduction of a mandatory process of agricultural collectivization, which was introduced incrementally. Private farming was prohibited, and those engaged in it were labeled as counter revolutionaries and persecuted. Restrictions on rural people were enforced through public struggle sessions, and social pressure. The Great Leap ended in catastrophe, resulting in tens of millions of excess deaths. Estimates of the death toll range from 18 million to at least 45 million. In subsequent conferences in 1960 and 1962, the negative effects of the Great Leap Forward were studied by the CPC, and Mao was criticized in the party conferences. Moderate Party members like Liu Shaoqi and Deng Xiaoping rose to power, and Mao was marginalized within the party, leading him to initiate the Cultural Revolution in 1966.