The Indonesian occupation of East Timor began in December 1975 and lasted until October 1999. After centuries of Portuguese colonial rule in East Timor, the 1974 Carnation Revolution in Portugal led to the decolonisation of its former colonies, creating instability in East Timor and leaving its future uncertain. After a small-scale civil war, the pro-independence Fretilin declared victory in the capital city of Dili and declared an independent East Timor on 28 November 1975.

Portuguese Timor was a colonial possession of Portugal that existed between 1702 and 1975. During most of this period, Portugal shared the island of Timor with the Dutch East Indies.