From October 1965 to March 1966, a series of large-scale killings and civil unrest primarily targeting members and supposed sympathizers of the Communist Party of Indonesia (PKI) took place in Indonesia. Other affected groups included alleged communist sympathisers, Gerwani women, trade unionists, ethnic Javanese Abangan, ethnic Chinese, atheists and other non-Muslims, and leftists in general. According to the most widely published estimates, at least 500,000 to 1 million people were killed. Some of the higher estimates reach figures as much as 2 to 3 million people killed.
The killings, sometimes described as a politicide and occasionally as a genocide, were instigated by the Indonesian Army under Suharto. Research and declassified documents demonstrate the Indonesian authorities received support from foreign countries such as the United States and the United Kingdom.
The killings began as an anti-communist purge following an attempted coup d'état by the 30 September Movement, which they self-proclaimed over media and communication outlets. It was a pivotal event in the transition to the "New Order" and the elimination of the PKI as a political force, with impacts on the global Cold War. The Army, after banning all independent news sources from publishing for a week, almost immediately pinned the abortive coup attempt to the PKI.
Concurrently, the intelligence agencies of the United States, United Kingdom, and Australia engaged in black propaganda campaigns against Indonesian communists. During the Cold War, the U.S. government and its Western allies had the goal of halting the spread of communism in addition to bringing countries into the sphere of Western Bloc influence. Separately, Britain had reasons for seeking Sukarno's removal, as his non-communist government was involved in an undeclared war with neighboring Malaysia, a Commonwealth federation of former British colonies.
Communists were purged from political, social, and military life in Indonesia, and the PKI itself was disbanded and banned. Mass killings began in October 1965, in the weeks following the coup attempt, and reached their peak over the remainder of the year before subsiding in the early months of 1966. They started in the capital, Jakarta, and spread to Central and East Java, and later Bali. Thousands of local vigilantes and army units killed actual and alleged PKI members, as well as members of other marginalized groups. Killings occurred across the country, with the most intense in the PKI strongholds of Central Java, East Java, Bali, and northern Sumatra. The upheavals led to the fall of Sukarno, who had been granted the title "President for life", and ushering in Suharto's three decades of pro-West authoritarian militaristic presidency.
The killings are skipped over in most Indonesian history textbooks and have received little attention by Indonesians due to their suppression under the Suharto regime, as well as lack of international attention. The search for satisfactory explanations for the scale and frenzy of the violence has challenged scholars from all ideological perspectives. The possibility of returning to similar upheavals is cited as a factor in the "New Order" administration's political conservatism and tight control of the political system. Vigilance and stigma against a perceived communist threat remained a hallmark of Suharto's doctrine, and it is still in force even today.
Despite a consensus at the highest levels of the U.S. and British governments that it would be necessary "to liquidate Sukarno", as related in a Central Intelligence Agency (CIA) memorandum from 1962,. which notes that, prior to the mid-1950s—by which time the relationship was in definite trouble—the US actually had, via the CIA, developed excellent contacts with Sukarno. and the existence of extensive contacts between anti-communist army officers and the U.S. military establishment – including the training of over 1,200 officers, "including senior military figures", and providing weapons and economic assistanceMacaulay, Scott (17 February 2014). The Act of Killing Wins Documentary BAFTA; Director Oppenheimer's Speech Edited Online. Filmmaker. Retrieved 12 May 2015. – the CIA denied active involvement in the killings. Declassified U.S. documents in 2017 revealed that the U.S. government had detailed knowledge of the mass killings from the beginning and was supportive of the actions of the Indonesian Army. U.S. complicity in the killings, which included providing extensive lists of PKI officials to Indonesian death squads, has been established by historians and journalists.
A top-secret CIA report from 1968 stated that the massacres "rank as one of the worst mass murders of the 20th century, along with the Soviet purges of the 1930s, the Nazi mass murders during the Second World War, and the Maoist bloodbath of the early 1950s."Mark Aarons (2007). "Justice Betrayed: Post-1945 Responses to Genocide." In David A. Blumenthal and Timothy L. H. McCormack (eds). The Legacy of Nuremberg: Civilising Influence or Institutionalised Vengeance? (International Humanitarian Law). Martinus Nijhoff Publishers. p. 81.
Background Support for Sukarno's presidency under his "Guided Democracy" depended on his forced and unstable "Nasakom" coalition between the military, religious groups, and communists. The rise in influence and the increasing militancy of the Communist Party of Indonesia (PKI), and Sukarno's support of it, was a source of serious concern for Muslims and the military, and tension grew steadily in the early and mid-1960s.Schwarz (1994), pp. 16–18 The third-largest communist party in the world,cf with Weiner (2007) p.259 the PKI had approximately 300,000 cadres and full membership of around two million.Cribb (1990), p. 41. The PKI largely aimed for its efforts to be non-violent, partially due to the party's political popularity in the country and established role in the Sukarno government. The party's assertive efforts to speed up land reform frightened those who controlled the land and threatened the social position of Muslim clerics.Schwarz (1994), pp. 17, 21. Sukarno required government employees to study his Nasakom principles as well as Marxist theory. He had met with Zhou Enlai, Premier of the People's Republic of China, and after this meeting had decided to create a militia, called the Fifth Force, which he intended to control personally. Sukarno ordered weapons from China to equip this Fifth Force. He declared in a speech that he favoured revolutionary groups whether they were nationalist, religious, or communist, stating, "I am a friend of the Communists because the Communists are revolutionary people."President Sukarno, speech on independence day, 17 August 1964 He said at a Non-Aligned Movement summit meeting in Cairo in October 1964 that his current purpose was to drive all of Indonesian politics to the left and thereby to neutralise the "reactionary" elements in the Army that could be dangerous for the revolution. Sukarno's international policies increasingly reflected his rhetoric.
Sukarno hosted the Bandung Conference in 1955 (in Bandung, Indonesia). It was a conference of mostly former colonised countries throughout Asia and Africa (including China, North Vietnam, Laos, and Cambodia). The conference was the predecessor to the Non-Aligned Movement and was not a communist convention. However, this was enough for the U.S. to be very suspicious of Sukarno and suspect him of deep communist sympathies.
Domestically, the PKI experienced rising popularity in Indonesia, with its performance increasing in elections throughout the 1950s. However, this also meant that tensions also increased when some communist party sympathizers attacked religious people in the villages, and accused landowners of being capitalists akin to the Dutch colonialists, increasing hatred towards the communists amongst the majority of conservative Indonesians. The PKI gained popularity amongst Indonesians because of their relatively low corruption and its accomplishment of its political goals. Rural polarization further increased after the PKI launched what it called "unilateral action" () to enforce at its own hands the earlier land reform laws of 1959 and 1960 that had gone unimplemented, resulting in clashes between militant peasants and militias affiliated with the landowners.Fibiger, Mattias. Suharto's Cold War: Indonesia, Southeast Asia, and the World. Oxford University Press, 2023, pg 42
As early as 1958, Western powers—in particular, the U.S. and the U.K.—pushed for policies that would encourage the Indonesian Army to forcefully act against the PKI and the Left, policies which included a covert propaganda campaign which was designed to damage the reputation of Sukarno and the PKI, and secret assurances along with military and financial support to anti-communist leaders within the Army. As approved by President Kennedy, the U.S. government supported the Army with its Territorial Management program, in which it gained inroads in local Indonesian communities by contributing to development.Philip W. Manhard et al., “Report of Civic Action Team to Indonesia,” U.S. Declassified Documents Online (Department of State, October 23, 1962). During Permesta and the West New Guinea dispute, the army gained a corrupt reputation because it hoarded rural resources. Local involvement allowed the army to re-establish itself, giving it basis to later carry out the killings.
The U.S. Central Intelligence Agency (CIA) considered assassinating Sukarno and selected an "asset" to do the job, but instead produced a pornographic film with an actor portraying Sukarno and a Soviet flight attendant to delegitimise him and paint him as a communist. However, the video was not released because the agency could not put together a convincing enough film.
30 September
On the evening of 30 September 1965, a group of militants, known as the 30 September Movement, captured and executed six of Indonesia's top military generals. The movement proclaimed itself as Sukarno's protectors, issuing a pre-emptive strike to prevent a possible coup by the "anti-Sukarno", pro-Western Council of Generals.
Following the execution, the movement's forces occupied Merdeka Square in Jakarta and the presidential palace. Shortly afterwards, however, President Sukarno refused to commit to the movement, for it had captured and assassinated many of his top generals. As the night continued, its poor leadership began to show, starting with a series of incoherent radio messages. The movement mainly aimed to occupy the main telecommunications building; however, it ignored the east side of the square, which was the location of Kostrad, the armed forces strategic reserve. At the time, Major General Suharto was in control of the reserve, and upon hearing the news of the takeover, he quickly capitalised on the movement's weaknesses, regaining control of the square without resistance. Following the surrender, the movement's troops did not take further action. At the same time, the Indonesian military slowly gained influence as Sukarno's waned, and within days, the government was under the control of Suharto. He immediately deployed troops and dispersed the movement while trumpeting the movement's actions as a "danger" to the nation.
A military propaganda campaign to link the coup attempt with the PKI, masterminded by Suharto and the military, began to sweep the country on 5 October (the Armed Forces Day and the day of the six generals' state funeral). Graphic images and descriptions of the murdered, tortured, and even castrated generals began to circulate the country. The campaign was successful despite falsified information, convincing both Indonesian and international audiences that the murders were a PKI attempt to undermine the government under President Sukarno. Though the PKI denied involvement, pent-up tension and hatred that had built up over the years were released.