On 1 October 1949 CCP chairman Mao Zedong proclaimed the People's Republic of China (PRC) from atop Tiananmen, after a near complete victory (1949) by the Chinese Communist Party (CCP) in the Chinese Civil War. The PRC is the most recent political entity to govern mainland China, preceded by the Republic of China (ROC; 1912–1949) and thousands of years of monarchical dynasties. The paramount leaders have been Mao Zedong (1949–1976); Hua Guofeng (1976–1978); Deng Xiaoping (1978–1989); Jiang Zemin (1989–2002); Hu Jintao (2002–2012); and Xi Jinping (2012 to present).Klaus Mühlhahn, Making China Modern: From the Great Qing to Xi Jinping (Harvard UP, 2019) pp 1–20.

The origins of the People's Republic can be traced to the Chinese Soviet Republic proclaimed in 1931, with the backing of the Communist Party of the Soviet Union, which included the Jiangxi and Yan'an Soviets,Qi'an, Zhang (), Cradle of the Republic: The Chinese Soviet Republic (), Xi'an: Shaanxi People's Press, 2003 in the midst of the Chinese Civil War against the Nationalist government only to dissolve in 1937. By 1949, the CCP took control of most of mainland China, and the ROC government retreated offshore to Taiwan. In 1950, the PRC captured Hainan from the ROC and annexed Tibet.

The CCP consolidated its popularity among the peasants through the Land Reform Movement, which included the state-tolerated executions of between 1 and 2 million landlords by peasants and former tenants. Though the PRC initially allied closely with the Soviet Union, the relations between the two communist nations gradually deteriorated, leading China to develop an independent industrial system and its own nuclear weapons. The Chinese population increased from 550 million in 1950 to 900 million in 1974. However, the Great Leap Forward, a massive industrialization project, resulted in an estimated 15 to 55 million deaths between 1959 and 1961, mostly from starvation. In 1964, China detonated its first atomic bomb. In 1966, Mao and his allies launched the Cultural Revolution, sparking a decade of political recrimination and social upheaval that lasted until Mao's death in 1976.

After Mao's death, the Gang of Four were arrested by Hua Guofeng and held responsible for the Cultural Revolution. The Cultural Revolution was rebuked, with millions rehabilitated. Deng Xiaoping took power in 1978, and started the reform and opening up, instituting large-scale political and economic reforms, together with the "Eight Elders", most senior and influential members of the party. The economic reforms marked China's transition away from planned economy. () China adopted its current constitution on 4 December 1982. In 1989, there were protests such those in Tiananmen Square, and then throughout the entire nation. Jiang Zemin was elevated to become the CCP general secretary, becoming the paramount leader. China's economy grew sevenfold during this time. British Hong Kong and Portuguese Macau returned to China in 1997 and 1999, respectively, as special administrative regions under the principle of one country, two systems. The country joined the World Trade Organization in 2001.

In 2002, Hu Jintao succeeded Jiang as the general secretary. Under Hu, China maintained its high rate of economic growth, overtaking the United Kingdom, France, Germany and Japan to become the world's second-largest economy. However, the growth also severely impacted the country's resources and environment, and caused major social displacement.China: Migrants, Students, Taiwan UC Davis Migration News January 2006 Xi Jinping succeeded as paramount leader in 2012. Shortly after his ascension to power, Xi launched a vast anti-corruption crackdown, that prosecuted more than 2 million officials by 2022. During his tenure, Xi has consolidated power unseen since the initiation of economic and political reforms. In the 21st century, its new wealth and technology led to a contest for primacy in Asian affairs versus India, Japan and the United States, and since 2018 a growing trade war with the United States.Jonathan Fenby, The Penguin History of Modern China: The Fall and Rise of a Great Power 1850 to the Present (2019).

Mao era (1949–1976)

Socialist transformation

Following the Chinese Civil War and victory of Mao Zedong's Communist forces over the Kuomintang forces of Generalissimo Chiang Kai-shek, who fled to Taiwan, Mao Zedong proclaimed the founding of the People's Republic of China (PRC) on 1 October 1949. Mao laid heavy theoretical emphasis on planned economy and class struggle, following Stalinism from the Soviet Union.

Between 1949 and 1953, Mao and the Chinese Communist Party (CCP) launched campaigns to persecute former landlords and merchants, known as the Land Reform Movement, starting the industrialisation program at the same time. Mao's goal was a total overhaul of the land ownership system, and extensive land reforms, including the execution of more powerful landlords. China's old system of gentry landlord ownership of farmland and tenant peasants was replaced with a distribution system in favor of poor/landless peasants which significantly reduced economic inequality, meanwhile over a million landlords were executed in the Chinese land reform.Stephen Rosskamm Shalom. Deaths in China Due to Communism. Center for Asian Studies Arizona State University, 1984. p. 24 The campaign resulted in hundreds of millions of peasants receiving a plot of land for the first time, and "middling peasants", who now accounted for 90% of the village population, owned 91% of the land.Walter Scheidel, The Great Leveler: Violence and the History of Inequality from the Stone Age to the Twenty-First Century (2017). However, between 1953 and 1956, further campaigns were launched by the CCP as "socialist transformation of ownership of the means of production"; the Communist Party began a collectivization campaign in villages across the country and peasants were forced to join agricultural production cooperatives and, as collective farming spread, peasants gave their land-use rights to these cooperatives.

On the other hand, the PRC officially passed and enacted its first Constitution in 1954, meanwhile continual political movements and class struggles were launched nationwide under Mao. Major political movements in the early 1950s included the Suppression of Counter-revolutionaries, the Three-anti and Five-anti Campaigns and the Sufan Movement, each of which resulted in a large number of deaths nationwide. Kuomintang officials and soldiers who remained in mainland China were purged during the Counterrevolutionaries Suppression Campaign (; 1950–1953), where reported over 1 million were executed. It was followed by the Three-Anti & Five-Anti Campaigns (;1951-1952), during which corrupt CCP officials and other "enemies of the people", mostly in cities, were purged or even summarily executed. The subsequent Hundred Flowers Campaign and Anti-Rightist Campaign of 1957–1958 significantly damaged the democracy in China, during which at least 550,000 people were persecuted, most of whom were intellectuals and political dissidents.Teiwes, Frederick C., and Warren Sun. 1999. China's road to disaster: Mao, central politicians, and provincial leaders in the unfolding of the great leap forward, 1955–1959. Contemporary China papers. Armonk, N.Y.: M.E. Sharpe. pp. 52–55. After the Anti-Rightist Campaign, China entered the de facto one-party state of the Chinese Communist Party.

Great Leap Forward and aftermath

Mao Zedong believed that socialism would eventually triumph over all other ideologies, and following the First Five-Year Plan (1953–1957) based on a Soviet-style centrally controlled economy, Mao took on the ambitious project of the "Great Leap Forward" in 1958, beginning an unprecedented process of collectivisation in rural areas, known as the "People's commune". Mao urged the use of communally organised iron smelters to increase steel production, pulling workers off of agricultural labor to the point that large amounts of crops rotted unharvested. Meanwhile, a nationwide large-scale campaign to eliminate sparrows (part of the Four Pests campaign) was launched in 1958 because Mao had heard complaints from farmers that sparrows were eating their grains, but the sparrow elimination campaign resulted in a major ecological disaster.

The implementation of Maoism thought in China may have been responsible for the deadliest famine in human history, in which 15–55 million people died due to starvation and epidemics. By the end of 1961, the birth rate was nearly cut in half because of malnutrition.MacFarquhar, Roderick. 1974. The origins of the Cultural Revolution. London: Published for Royal Institute of International Affairs, East Asian Institute of Columbia University and Research Institute on Communist Affairs of Columbia by Oxford University Press. p. 4. In 1958, the Xunhua uprising broke out and in 1959, a major uprising erupted in Tibet, resulting in the deaths of tens of thousands of Tibetans, and the Dalai Lama went into exile afterwards. Meeting criticisms from Marshal Peng Dehuai and others at the Lushan conference over the radical policies, Mao launched the massive "Anti-Right Deviation Struggle" in 1959, during which over 3 million CCP members were labelled as "right-deviationists" or "right-opportunists" and were subsequently purged or penalized. During the Great Famine, a special supply system (or tegong) was established nationwide in 1960, providing food and daily necessities exclusively to high-ranking officials of the CCP and Chinese government.

Mao's failure with the Leap reduced his power in government, whose administrative duties fell to President Liu Shaoqi and Deng Xiaoping, especially after the Seven Thousand Cadres Conference in early 1962. Liu, Deng and other leaders allowed limited economic and market reform such as sanzi yibao, which were viewed by Mao as means to destroy the socialism. The power struggle between Mao Zedong and Liu Shaoqi together with Deng Xiaoping began since 1962. The Socialist Education Movement was launched by Mao from 1963 to 1965, as a result.

Much more successful was the "Two Bombs, One Satellite" program, launched in 1958, with the help at first of Moscow.. It used leading scientists who returned to mainland China from abroad, including Qian Xuesen, Deng Jiaxian and Qian Sanqiang. China's first atomic bomb, nuclear missile, hydrogen bomb and artificial satellite were all successfully developed by 1970. However, the program had been seriously affected by the Great Leap Forward and the Cultural Revolution.

Third Front

After the failure of the Great Leap Forward, China's leadership slowed the pace of industrialization. It invested more on in China's coastal regions and focused on the production of consumer goods. After an April 1964 General Staff report concluded that the concentration of China's industry in its major coastal cities made it vulnerable to attack by foreign powers, Mao argued for the development of basic industry and national defense industry in protected locations in China's interior. This resulted in the building of the Third Front, which involved massive projects including railroad infrastructure, aerospace industry including satellite launch facilities, and steel production industry including Panzhihua Iron and Steel.