Question: When did the country in which Wong Chen resided gain independence from Great Britain?

full_context: Document 1: Andrew Cheng: Andrew Cheng Kar-foo () (born 28 April 1960 in Hong Kong) was a Hong Kong politician and solicitor. He is a former Democratic Party member of the Legislative Council of Hong Kong representing the New Territories East geographical constituency.
Document 2: History of Malaysia: Japanese invasion during World War II ended British domination in Malaysia. The subsequent occupation of Malaya, North Borneo and Sarawak from 1942 to 1945 unleashed nationalism. In the Peninsula, the Malayan Communist Party took up arms against the British. A tough military response was needed to end the insurgency and bring about the establishment of an independent, multi-racial Federation of Malaya on 31 August 1957. On 22 July 1963, Sarawak was granted a self - governance. The following month on 31 August 1963, both North Borneo and Singapore were also granted self - governance and all states began to formed Malaysia on 16 September 1963. Approximately two years later, the Malaysian parliament passed a bill without the consent of signatory of Malaysia Agreement 1963 to separate Singapore from the Federation. A confrontation with Indonesia occurred in the early - 1960s. Race riots in 1969 led to the imposition of emergency rule, and a curtailment of political life and civil liberties which has never been fully reversed. Since 1970 the ``Barisan Nasional coalition ''headed by United Malays National Organisation (UMNO) has governed Malaysia until the
Document 3: Fan Yew Teng: Fan Yew Teng (范俊登 12 May 1942 – 7 December 2010) was former Acting Secretary-General of the Democratic Action Party, Malaysia, former Member of Parliament for Kampar (elected in 1969) and Menglembu (elected in 1974), and former Selangor State Assemblyman for Petaling Jaya. He was arrested in 1969 and later charged under the Sedition Act for publishing, as editor of DAP's The Rocket, a speech by Dr. Ooi Kee Saik, then Penang DAP Chairman. He was eventually convicted for sedition in 1975. Fan was then disqualified from Parliament and denied all MP privileges, including his pension. He kept his parliamentary seat until 1977, when the Privy Council upheld the decision of the High Court. Fan left DAP over differences in 1978 to join Social Democratic Party (SDP). He rejoined the DAP in 1998, during the transformative period of Reformasi in Malaysia.
Document 4: Chua Soi Lek: Tan Sri Datuk Seri Dr. Chua Soi Lek (); born 2 January 1947, also known as Chua Kin Seng, is a Chinese Malaysian politician from the state of Johor. He is the 9th President of the Malaysian Chinese Association (MCA), a major component party in Barisan Nasional (BN) coalition. He held the post of Minister of Health from 2004 until 2008.
Document 5: Private school: After Malaysia's independence in 1957, the government instructed all schools to surrender their properties and be assimilated into the National School system. This caused an uproar among the Chinese and a compromise was achieved in that the schools would instead become "National Type" schools. Under such a system, the government is only in charge of the school curriculum and teaching personnel while the lands still belonged to the schools. While Chinese primary schools were allowed to retain Chinese as the medium of instruction, Chinese secondary schools are required to change into English-medium schools. Over 60 schools converted to become National Type schools.
Document 6: Wong Chen: Wong Chen (; born 18 December 1968) is a Malaysian politician and is the Member of the Parliament of Malaysia for the (Subang Jaya seat, formerly known as Kelana Jaya) constituency in Selangor. He is a member of Parti Keadilan Rakyat (PKR) in the Pakatan Harapan (PH) ruling coalition.
Document 7: Lee Boon Chye: Dr. Lee Boon Chye (; born 26 September 1959) is a Malaysian politician and currently serving as the Deputy Minister of Health of Malaysia. He is the incumbent Member of the Parliament of Malaysia for the Gopeng constituency in Perak. He is also a vice-president of the Parti Keadilan Rakyat (PKR), a component party in the Pakatan Harapan (PH) government coalition.
Document 8: 2018 Malaysian general election: Pakatan Harapan, the main opposition coalition in the Malaysian Parliament, won 113 seats in the Dewan Rakyat, Malaysia's lower house of parliament. The Sabah Heritage Party, which won another 8 seats, informally aligned itself with Pakatan Harapan, giving the opposition alliance a total of 121 seats in the new Parliament, enough to form a government.
Document 9: Malaysia: Malaysia has its origins in the Malay kingdoms which, from the 18th century, became subject to the British Empire, along with the British Straits Settlements protectorate. Peninsular Malaysia was unified as the Malayan Union in 1946. Malaya was restructured as the Federation of Malaya in 1948, and achieved independence on 31 August 1957. Malaya united with North Borneo, Sarawak, and Singapore on 16 September 1963 to become Malaysia. In 1965, Singapore was expelled from the federation.The country is multi-ethnic and multi-cultural, which plays a large role in its politics. About half the population is ethnically Malay, with large minorities of Malaysian Chinese, Malaysian Indians, and indigenous peoples. While recognising Islam as the country's established religion, the constitution grants freedom of religion to non-Muslims. The government system is closely modelled on the Westminster parliamentary system and the legal system is based on common law. The head of state is the king, known as the Yang di-Pertuan Agong. He is an elected monarch chosen from the hereditary rulers of the nine Malay states every five years. The head of government is the Prime Minister. The country's official language is Malaysian, a standard form of the Malay language. English remains an active second language.
Document 10: History of Singapore: During World War 2, Singapore was conquered and occupied by the Japanese Empire from 1942 to 1945. When the war ended, Singapore reverted to British control, with increasing levels of self-government being granted, culminating in Singapore's merger with the Federation of Malaya to form Malaysia in 1963. However, social unrest and disputes between Singapore's ruling People's Action Party and Malaysia's Alliance Party resulted in Singapore's expulsion from Malaysia. Singapore became an independent republic on 9 August 1965.
Document 11: History of Malaysia: The Malayan Emergency as it was known, lasted from 1948 to 1960, and involved a long anti-insurgency campaign by Commonwealth troops in Malaya. The British strategy, which proved ultimately successful, was to isolate the MCP from its support base by a combination of economic and political concessions to the Chinese and the resettlement of Chinese squatters into “New Villages” in “white areas” free of MCP influence. In December 1948, 24 villagers were executed by British troops. From 1949 the MCP campaign lost momentum and the number of recruits fell sharply. Although the MCP succeeded in assassinating the British High Commissioner, Sir Henry Gurney, in October 1951, this turn to terrorist tactics alienated many moderate Chinese from the Party. The arrival of Lt.-Gen Sir Gerald Templer as British commander in 1952 was the beginning of the end of the Emergency. Templer invented the techniques of counter-insurgency warfare in Malaya and applied them ruthlessly. Although the insurgency was defeated Commonwealth troops remained with the backdrop of the Cold War. Against this backdrop, independence for the Federation within the Commonwealth was granted on 31 August 1957, with Tunku Abdul Rahman as the first prime minister.
Document 12: Chris Wang: Yi-Ju Christopher Wang, commonly known as Chris Wang (born May 15, 1977, ) is an African National Congress member of the National Assembly of South Africa. He was the youngest MP of the country when elected in 2004.
Document 13: 2018 Malaysian general election: This marked a historic defeat for the ruling Barisan Nasional coalition, which had been the governing party of Malaysia and its predecessor state, Malaya, since the country's independence in 1957. This makes Mahathir Mohamad the next Prime Minister of Malaysia and, at 92 years old, the oldest head of government in the world, although he has indicated he would give way within a few years to jailed opposition leader Anwar Ibrahim after seeking a royal pardon for him.
Document 14: British Empire: Following the defeat of Japan in the Second World War, anti-Japanese resistance movements in Malaya turned their attention towards the British, who had moved to quickly retake control of the colony, valuing it as a source of rubber and tin. The fact that the guerrillas were primarily Malayan-Chinese Communists meant that the British attempt to quell the uprising was supported by the Muslim Malay majority, on the understanding that once the insurgency had been quelled, independence would be granted. The Malayan Emergency, as it was called, began in 1948 and lasted until 1960, but by 1957, Britain felt confident enough to grant independence to the Federation of Malaya within the Commonwealth. In 1963, the 11 states of the federation together with Singapore, Sarawak and North Borneo joined to form Malaysia, but in 1965 Chinese-majority Singapore was expelled from the union following tensions between the Malay and Chinese populations. Brunei, which had been a British protectorate since 1888, declined to join the union and maintained its status until independence in 1984.
Document 15: National Monument (Malaysia): The National Monument is a sculpture that commemorates those who died in Malaysia's struggle for freedom, principally against the Japanese occupation during World War II and the Malayan Emergency, which lasted from 1948 until 1960. It is located in the Federal capital, Kuala Lumpur. The Malaysian Houses of Parliament are situated near the monument.
ground_truth: 31 August 1957
sub_queries: In which country did Wong Chen live? Answer: Malaysia
when did Malaysia gain independence from great britain Answer: 31 August 1957