The opening of two casinos in 2010, the SARS outbreak in 2003 and the major MRT breakdowns in 2011 were historical events that most Singaporeans knew about.
This was revealed on Sunday after 1,500 Singaporeans were asked about 50 major historical events between 1819 and 2011 in a survey conducted by the Institute of Policy Studies (IPS).
The survey's lead researcher, Dr Leong Chan-Hoong, senior research fellow at IPS, said: "The findings suggest that when it comes to awareness of historical events, those related to bread-and-butter issues, rather than broad over-arching political events, feature strongly in people's memories."
Below were the five significant events that Singaporeans were least aware of:
PAP SPLIT (1961)
32.1 per cent of Singaporeans surveyed aware of the incident
The now-defunct Barisan Sosialis was formed on July 29, 1961, by expelled left-wing members of the People's Action Party (PAP).
They had opposed the formation of the Federation of Malaysia consisting of Malaya, Singapore, Sarawak, North Borneo and Brunei.
GRADUATE MOTHERS SCHEME (1984)
24.9 per cent
In 1984, the Government gave education and housing priorities, tax rebates and other benefits to mothers with a university degree, and their children.
For instance, the children of graduate mothers would benefit from a priority scheme for registration of Primary One Children.
Then-Prime Minister Lee Kuan Yew was concerned that educated women were less likely to marry and have children as compared to women with lower education levels.
Most parts of the scheme, which drew fierce debate, were eventually scrapped in 1985.
THE LAJU INCIDENT (1974)
22.1 per cent
Four men armed with submachine guns and explosives tried to blow up the Shell Oil Refinery on Pulau Bukom Besar, hijacked the ferryboat Laju at the Bukom jetty and held five crew members as hostages on Jan 31, 1974.
After negotiations, the group surrendered its arms, released the hostages and boarded a specially-arranged Japan Airlines (JAL) aircraft to Kuwait on Feb 8.
On board with the hijackers were 13 Singapore government representatives - acting as guarantors - led by Mr S R Nathan, who was then the director of Security and Intelligence Division at the Ministry of Defence. They were back in Singapore the following day.
MARXIST CONSPIRACY (1987)
18.5 per cent
The Ministry of Home Affairs arrested 16 people under the Internal Security Act (ISA) for their involvement in a "Marxist conspiracy" to topple the government in May 1987.
Those arrested were mostly English-educated, with a mix of church workers, social workers, graduates and professionals.
By December 1987, all the detainees had been released except for Vincent Cheng Kim Chuan, who was said to be the key assistant of the conspiracy's mastermind Tan Wah Piow.
Tan, who is still based in Britain, fled Singapore in 1976 after evading national service.
OPERATION COLDSTORE (1963)
16.6 per cent
Operation Coldstore was launched on Feb 2, 1963, against the backdrop of Singapore's merger with Malaya, which would take place in September.
Under the Preservation of Public Security Ordinance Act, the Special Branch initially arrested 107 people, among them key leaders of Barisan Sosialis and associated pro-communist organisations, who opposed the merger.
The communist network in Singapore, which was accused of trying to mount violence or disorder to oppose the merger with, was dealt a harsh blow after Operation Coldstore. The merger went ahead without major incident.
This article was first published on January 28, 2015.
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