But the roots of the Cultural Revolution go back much further and stretch beyond China’s borders.

The movement also resulted in a dramatic and yet unexpected shift in foreign policy towards pragmatism, a change that shaped global geopolitics for years to come and ran counter to the direction at home.

The origins of the Cultural Revolution go back to the death of Soviet dictator Joseph Stalin and his subsequent denunciation by successor Nikita Khrushchev in the mid 1950s. At the 20th congress of the Soviet Union’s Communist Party, Khrushchev denounced the personality cult around the dead leader. Khrushchev also ushered in a degree of relaxation of the media and introduced a series of economic reforms.

Warren Sun, professor of Chinese studies at Monash University, said Mao was concerned that the Chinese Communist Party was moving in a similarly revisionist direction, emphasising expertise rather than ideological purity.

Sun said Mao saw Liu and his close ally Deng Xiaoping as Khrushchev’s “agents” in China, undermining his own place at the head of Chinese politics.

“The deteriorating Sino-Soviet relations that followed the early 1960s polemics against Khrushchev’s revisionism and Soviet hegemony clearly figured prominently in the mix of what prompted Mao to launch the Cultural Revolution,” Sun said.

Edward Friedman, an expert on China elite politics at the University of Wisconsin-Madison, agreed that the response to Stalin’s death was pivotal in the birth of the Cultural Revolution.

“Mao was China’s Stalin. And Mao wishes to lead the world anti-imperialist movement, and so he has to discredit Khrushchev,” Friedman said.

“His foreign policy is anti Soviet. And any enemy of the Soviets can be Mao’s friends – the Shah [of Iran], [Chile’s Augusto] Pinochet, [Angola’s] Holden Roberto, [Cambodia’s] Pol Pot.”

The split with the Soviet Union was cemented by the 1968 Soviet invasion of Czechoslovakia, the seven-month undeclared military conflict between China and the Soviet Union in 1969 and the subsequent rise of the Brezhnev doctrine, a Soviet foreign policy that sought to unite all its socialist allies to fight the US-led West.

Gradually, Mao started to see Soviet Union as a greater threat than the United States. He concluded at one point that a nuclear conflict with the Soviets was unavoidable and mobilised the whole nation to prepare for it.

By turning its back on the Soviet Union, China was isolating itself diplomatically in the cold war world. Now it was distanced not only from the US-led capitalist West but also the Soviet-led socialist bloc, except for a few socialist allies who were openly critical of the Soviet Union like Albania and Romania. In addition, China’s relations with many of its neighbours had soured with its 1962 border war with India and the widespread anti-China riots in Southeast Asia in the early 1960s.

It all added up to a sense of insecurity, according to Fabio Lanza, a historian focused on modern communist-ruled China and an expert on Mao at the University of Arizona.

Lanza said that while he believed the causes of the Cultural Revolution seemed to be mostly internal,“one can argue that Mao’s idea of the possible overthrow of communism was connected with a profound sense of insecurity generated in part by those international circumstances”.

That all changed with Mao’s push for anti-revisionism. The Cultural Revolution reverberated throughout the global left, with Mao claiming that the Soviet Union had betrayed revolutionary struggles throughout the world.

China threw its support behind liberation struggles in Vietnam, Africa and Palestine. It championed the idea of a global movement in which “the countryside” would finally conquer the cities, echoing struggles during China’s long civil war.

The broader idea was to shift geopolitics from the “two camps” theory – the socialist and capitalist blocs – to one dominated by global radical revolutionary and national independence movements.

“The China of the Cultural Revolution was perceived to be a beacon of hope among world radicals,” Lanza said.

Under his “three worlds” strategy, Mao sought to build a broad united front of all forces that could be directed against the principal enemy or enemies of the people of the world.

He had become convinced that the developing world or third world would become the battlefield on which the power of the West could be destroyed and the world revolution could be started, and that China, instead of the Soviet Union, would be the leader of this historic struggle.

During the heady days of the Cultural Revolution, only representatives of friendly nations and revolutionary parties in Asia, Africa and Latin America – as well as ideological sympathisers from elsewhere – visited Beijing.

Beijing played up China’s status as an “oppressed coloured people” as a means to oppose the Soviets and American and Europeans.

The Cultural Revolution strengthened the revolutionary internationalist orientation that defined Chinese foreign policy during those years.

Sun said that inevitably in the early stage of the Cultural Revolution, China’s foreign interests were sacrificed to the pursuit of ideological purity.

“Overall, no foreign government or political party – whether imperialist or revisionist – could escape the People’s Republic’s disdain if it refused to toe the Maoist line of world revolution. Consequently, China entered a period of extreme isolationism,” Sun said.

That tide turned in an unexpected direction with the release of a report that even today is little known in China.

On February 19, 1969, Mao appointed four marshals – Chen Yi, Xu Xiangqian, Nie Rongzhen and Ye Jianying – to lead a secret work group to examine two basic questions: was the Soviet Union or the US the bigger threat to China, and just how great was the chance of a major war?

On September 17, they concluded that China was not in danger of a major war and the Soviet Union was a bigger threat than the US. They recommended China stall any possibility of hostilities until the country could improve its economic, military, social and political positions.

The report’s impact was huge – some say it led to the establishment of a de facto China-US anti-Soviet alliance, paving the way for China’s eventual opening up to embrace global capitalism in the post-Mao era.

Beijing also toned down its rhetoric against the capitalist West following trips to China in the early 1970s by then US secretary of state Henry Kissinger and US president Richard Nixon, which represented a complete reversal of China’s international stance.

Still, some historians said that Mao paid little concern to foreign relations during the Cultural Revolution as Beijing did not take action to stop Red Guard attacks on the British and Soviet embassies. Red Guards and party-controlled media also fired broadsides at American imperialism as well as Soviet revisionism.

But Mao’s diplomatic manoeuvring – both in the third world and with the US – succeeded in winning Beijing back its seat at the United Nations, replacing Taipei as the legitimate government of China in 1971. That development promoted China’s status on the world stage and its engagement with the outside world, in particular the West.

Hongyi Lai, a professor of contemporary Chinese studies and politics at the University of Nottingham, said the Cultural Revolution helped drive the global push for national liberation and the fight against oppression from privileged elites and the entrenched interests in the Soviet bloc.

But Lai said China also lost many friends around the world.

“While Mao emerged as a leader for the oppressed and was welcomed by the radical intellectuals, he was feared by many,” Lai said.

Lanza said Maoism influenced a generation of European and Indian intellectuals, and the links between Maoist intellectuals and workers and other social groups laid the groundwork for advocacy work in the following decades.

“I find that reductive of the role of Maoism but it is a part of the process,” Lanza said.

Overall, the Cultural Revolution did not lead to Beijing’s further diplomatic isolation but an improvement of foreign relations, with its UN reinstatement in 1971 and normalisation of relations with the US-led West following Nixon’s visit to Beijing in 1972.

“Paradoxically, while Mao’s opposition to revisionism, the overarching theme of the Cultural Revolution, created the disaster of ‘civil war and total chaos’ within China, it resulted in remarkable diplomatic achievements and greatly improved China’s standing in the international community,” Sun said.