Portuguese Timor significant event Indonesian invasion of East Timor
End of Portuguese rule
Following a 1974 coup (the "Carnation Revolution"), the new Government of Portugal favoured the immediate decolonisation process for Portuguese territories in Asia and Africa. When Portuguese Timorese political parties were first legalised in April 1974, three major players emerged. The Timorese Democratic Union (UDT) was dedicated to preserving Portuguese Timor as a protectorate of Portugal, and in September announced its support for independence. It was formed by members of the existing National Action Party and plantation owners. Fretilin, formed by trade unionists and anti-colonialists, endorsed "the universal doctrines of socialism", as well as "the right to independence", and later declared itself "the only legitimate representative of the people". A third party, APODETI, emerged advocating Portuguese Timor's integration with Indonesia expressing concerns that an independent East Timor would be economically weak and vulnerable. Smaller political parties included the Association of Timorese Heroes, a party advocating union with Australia, and the Timorese Labour Party. The rapid political changes fed down to the local level, where political allegiance was affected by existing internal divisions and intra-suco divisions.: 125 On 14 November 1974, Mário Lemos Pires - an Army officer - was appointed by the new Portuguese Government as Governor and Commander-in-Chief of Portuguese Timor.
Meanwhile, the political dispute between the Portuguese Timorese parties soon gave rise to an armed conflict, that included the participation of members of the Colonial Police and Timorese soldiers of the Portuguese Army.
In August, a UDT faction seized control of government buildings in Dili and began to arrest members of Fretilin. While hundreds were arrested, most of the Fretilin leadership escaped south to Aileu. While there were some similar actions in other towns, UDT was unable to build upon its initial surprise action. Fretilin, with the support of much of the former colonial armed forces, began a counter-attack on 20 August.: 123–124 Unable to control the conflict with the few Portuguese troops that he had at his disposal, Lemos Pires decided to leave Dili with his staff and transfer the seat of the administration to Atauro Island (located 25 km off Dili) in late August 1975. At the same time, he requested Lisbon to send military reinforcements, the request being responded with the sending of a warship, the NRP Afonso Cerqueira, which arrived in Portuguese Timorese waters in early October.
On 28 November 1975, Fretilin unilaterally declared the colony's independence, as the Democratic Republic of East Timor (República Democrática de Timor-Leste).
Representatives of UDT and APODETI, encouraged by Indonesian intelligence, declared that the territory should become part of Indonesia.On 7 December 1975, the Indonesian Armed Forces launched an invasion of East Timor. At 3:00 a.m., the two Portuguese corvettes, the NRP João Roby and NRP Afonso Cerqueira, anchored near Atauro, detected on the radar a high number of unidentified air and naval targets approaching. They soon identified the targets as Indonesian military aircraft and warships, which initiated an assault against Dili. Lemos Pires and his staff then left Atauro, embarked on the Portuguese warships, and headed to Darwin in the Northern Territory of Australia.
The João Roby and Afonso Cerqueira were ordered to continue patrolling the waters around the former Portuguese Timor, in preparation of possible military action to respond to the Indonesian invasion, constituting the naval task force UO 20.1.2 (latter renamed FORNAVTIMOR).  Portugal sent a third warship to the region, the NRP Oliveira e Carmo, which arrived on 31 January 1976 and replaced the NRP Afonso Cerqueira.  The Portuguese warships would continue in the region until May 1976, when the remaining NRP Oliveira e Carmo left, going back to Lisbon, at a time when a military action to expel the Indonesian forces was clearly seen as unviable.
On 17 July 1976, Indonesia formally annexed East Timor, declaring it as its 27th province and renaming it Timor Timur.  The United Nations, however, did not recognise the annexation, continuing to consider Portugal as the legal Administering Power of what under international law was still Portuguese Timor.
Following the end of Indonesian occupation in 1999, and a United Nations administered transition period, East Timor became formally independent 20 May 2002.