30 September Movement — 1965 Indonesian military faction that attempted a coup
The failed coup triggered a mass anti-communist purge in Indonesia, leading to hundreds of thousands of deaths and the fall of President Sukarno.
Key Facts
- Date of coup attempt
- 1 October 1965 (early hours)
- Army generals assassinated
- 6
- Total senior officers killed
- 8
- Also known as
- Gestapu / G30S / G30S/PKI
- Challenging academic work
- Cornell Paper by Anderson & McVey, 1971
By the Numbers
Location
Cause → Event → Consequence
Deep ideological tensions within Indonesia between the military and the Communist Party of Indonesia (PKI) came to a head in 1965. PKI leaders and sympathizers within the armed forces grew alarmed at the influence of anti-communist army generals and moved to preempt what they feared was an imminent military takeover, allegedly with some awareness or involvement by President Sukarno, though his precise role remains disputed.
In the early hours of 1 October 1965, the Thirtieth of September Movement assassinated six Indonesian Army generals in Jakarta in an attempted coup. The movement briefly declared control over key media and communications and claimed to have taken President Sukarno under its protection. By the end of that day the coup had collapsed in Jakarta, though fighting continued in central Java until two additional senior officers were killed.
The army, backed by socio-political and religious groups, blamed the PKI for the coup. A sweeping anti-communist purge followed, resulting in the imprisonment and deaths of hundreds of thousands of actual or suspected PKI members and sympathizers. The events led to the political downfall of President Sukarno and the rise of General Suharto, who established the New Order government and ruled Indonesia for over three decades.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Sukarno (role disputed).
Side B
1 belligerent
Suharto.