- 12 September 1984 – during the Tanjung Priok massacre, 24 people were killed and 54 injured.
- 21 September 1629 – during the Siege of Batavia, the Dutch governor Jan Pieterszoon Coen died and was buried in Batavia (now Jakarta).
- 30 September 1965 – The Thirtieth of September Movement (pictured) assassinated 6 Indonesian Army generals in an abortive coup d'état by Communist Party of Indonesia in Lubang Buaya.