Mao Zedong (26 December 1893 – 9 September 1976) was a Chinese politician, revolutionary, and political theorist who founded the People's Republic of China (PRC) in 1949 and led the country from its establishment until his death in 1976. Mao served as chairman of the Chinese Communist Party (CCP) from 1943 until his death, and as the party's de facto leader from 1935. His theories, which he advocated as a Chinese adaptation of Marxism–Leninism, are known as Maoism.

Born to a peasant family in Shaoshan, Hunan, Mao studied in Changsha and was influenced by the 1911 Revolution and ideas of Chinese nationalism and anti-imperialism. He was introduced to Marxism while working as a librarian at Peking University, and later participated in the May Fourth Movement of 1919. In 1921, Mao became a founding member of the CCP. After the start of the Chinese Civil War between the Kuomintang (KMT) and CCP, Mao led the failed Autumn Harvest Uprising in Hunan in 1927, and in 1931 founded the Jiangxi Soviet. He helped build the Chinese Red Army, and developed a strategy of guerilla warfare. In 1935, Mao became leader of the CCP during the Long March, a military retreat to the Yan'an Soviet in Shaanxi, where the party began rebuilding its forces. The CCP allied with the KMT in the Second United Front at the start of the Second Sino-Japanese War in 1937, but the civil war resumed after Japan's surrender in 1945. In 1949, Mao's forces defeated the Nationalist government, which withdrew to Taiwan.

On 1 October 1949, Mao proclaimed the foundation of the PRC, a one-party state controlled by the CCP. He initiated land redistribution and industrialisation campaigns, suppressed political opponents, intervened in the Korean War, and oversaw the ideological Hundred Flowers and Anti-Rightist Campaigns. From 1958 to 1962, Mao oversaw the Great Leap Forward, a campaign which aimed to rapidly collectivise agriculture and industrialise the country. It failed, and resulted in the Great Chinese Famine. In 1966, Mao launched the Cultural Revolution, which was marked by violent class struggle, destruction of historical artifacts, and Mao's cult of personality. From the late 1950s, Mao's foreign policy was dominated by a political split with the Soviet Union, and in the 1970s he began establishing relations with the United States. In 1976, Mao died of a heart attack. He was initially succeeded by Hua Guofeng, then in 1978 by Deng Xiaoping. The CCP's official evaluation of Mao's legacy both praises him and acknowledges mistakes in his later years.

Mao's policies resulted in a vast number of deaths, with tens of millions of victims of famine, political persecution, prison labour and executions, and his regime has been described as totalitarian. Mao has also been credited with transforming China from a semi-colony to a major world power and advancing literacy, women's rights, basic healthcare, education, and life expectancy. In modern China, he is widely regarded as a national hero who liberated the country from imperialism. He became an ideological leader within the international communist movement, inspiring various Maoist organisations.

During Mao's lifetime, the English-language media universally rendered his name as Mao Tse-tung, using the Wade–Giles system of transliteration though with the circumflex accent in the syllable Tsê dropped. Due to its recognizability, the spelling was used widely, even by the PRC's foreign ministry after Hanyu Pinyin became the PRC's official romanisation system for Mandarin Chinese in 1958; the well-known booklet of Mao's political statements was officially entitled Quotations from Chairman Mao Tse-tung in English translations. While the pinyin-derived spelling Mao Zedong is increasingly common, the Wade–Giles-derived spelling Mao Tse-tung continues to be used in modern publications to some extent.

Mao Zedong was born on 26 December 1893, near Shaoshan village in Hunan, during the Qing dynasty. His father, Mao Yichang, was a formerly impoverished peasant who had become one of the wealthiest farmers in Shaoshan. Growing up in rural Hunan, Mao described his father as a stern disciplinarian, who would beat him and his three siblings, the boys Zemin and Zetan, as well as an adopted sister/cousin, Zejian. Mao's mother, Wen Qimei, was a devout Buddhist who tried to temper her husband's strict attitude. Mao too became a Buddhist, but abandoned this faith in his mid-teenage years. At age 8, Mao was sent to Shaoshan Primary School. Learning the value systems of Confucianism, he later admitted that he did not enjoy the classical Chinese texts preaching Confucian morals, instead favouring classic novels like Romance of the Three Kingdoms and Water Margin. At age 13, Mao finished primary education, and his father united him in an arranged marriage to the 17-year-old Luo Yixiu, thereby uniting their land-owning families. Mao refused to recognise her as his wife, becoming a fierce critic of arranged marriage and temporarily moving away. Luo was locally disgraced and died of dysentery in 1910 at 20 years old. Working on his father's farm, Mao read voraciously and developed a "political consciousness" from Zheng Guanying's booklet which lamented the deterioration of Chinese power and argued for the adoption of representative democracy. Mao also read translations of works by Western authors including Adam Smith, Montesquieu, Jean-Jacques Rousseau, Charles Darwin, and Thomas Huxley. Interested in history, Mao was inspired by the military prowess and nationalistic fervour of George Washington and Napoleon Bonaparte. His political views were shaped by Gelaohui-led protests which erupted following a famine in Changsha, the capital of Hunan; Mao supported the protesters' demands, but the armed forces suppressed the dissenters and executed their leaders. The famine spread to Shaoshan, where starving peasants seized his father's grain. He disapproved of their actions as morally wrong, but claimed sympathy for their situation. At age 16, Mao moved to a higher primary school in nearby Dongshan, where he was bullied for his peasant background.

In 1911, Mao began middle school in Changsha. Revolutionary sentiment was strong in the city, where there was widespread animosity towards Emperor Puyi's absolute monarchy and many were advocating republicanism. The republicans' figurehead was Sun Yat-sen, an American-educated Christian who led the Tongmenghui society. In Changsha, Mao was influenced by Sun's newspaper, The People's Independence (Minli bao), and called for Sun to become president in a school essay. As a symbol of rebellion against the Manchu monarch, Mao and a friend cut off their queue pigtails, a sign of subservience to the emperor.

Inspired by Sun's republicanism, the army rose up across southern China, sparking the Xinhai Revolution. Changsha's governor fled, leaving the city in republican control. Supporting the revolution, Mao joined the rebel army as a private soldier, but was not involved in fighting or combat. The northern provinces remained loyal to the emperor, and hoping to avoid a civil war, Sun—proclaimed "provisional president" by his supporters—compromised with the monarchist general Yuan Shikai. The monarchy was abolished, creating the Republic of China, but the monarchist Yuan became president. With the revolution over, Mao resigned from the army in 1912, after six months as a soldier. Around this time, Mao discovered socialism from a newspaper article; proceeding to read pamphlets by Jiang Kanghu, the student founder of the Chinese Socialist Party, Mao remained interested yet unconvinced by the idea.