Timeline of the Singapore in World War 2

British Singapore (Pre-WWII)

1819: British East India Company established Singapore as a trading post
1826: Britain established Singapore, Malacca, and Penang as colonies of the Strait Settlements
1832: Singapore became the capital of the Strait Settlements
1867: Strait Settlements officially became a crown colony of the British Empire
1869: Suez Canal officially opened
1922: Singapore became the main British naval base in East Asia

Battale of Singapore (1941 - 1942)

December 10, 1941: Japanese troops sank two British warships
December 30, 1941: Martial law declared in Singapore
January 8, 1942: Japanese troops penetrated outer lines of defense at Kuala Lumpur, Malaya
January 15, 1942: Japanese troops captured Muar. British troops in Malaya retreat to Singapore
January 17, 1942: British blew up causeway that linked Malaya and Singapore to prevent Japanese troops from entering
January 30, 1942: All British troops withdrew from Mayala. Within 55 days, Britain lost the Malaya Peninsula, beginning the siege of Singapore
February 1, 1942: Japanese troops repaired the destroyed causeway to reach Singapore
February 5, 1942: Japanese troops attacked Pulau Ubin
February 8, 1942: Japanese troops landed in northwest Singapore
February 10, 1942: British Royal Air Force withdrew a small number of aircraft from Singapore
February 11, 1942: Japanese troops attacked Indian, Chinese, and British troops in Singapore’s Chao Chu Kang and Bukit Timah Roads
February 13, 1942: 1st and 2nd Malay Regiment and Japanese troops battled for two days at Bukit Chandu
February 14, 1942: Japanese troops attacked Alexandra Barracks Hospital
February 15, 1942: Britain surrendered Singapore to Japan

Japanese Occupation (1942 - 1945)

February 18, 1942: Sook Ching Massacre
September 26, 1943: Explosion of seven Japanese vessels on the Singapore Harbor
October 10, 1943: Double Tenth Incident
December 1943: Japanese Central Military Administration created labor service corps in Singapore and Malaya​

Return to British Rule (Post WWII)

August 15, 1945: British Military Administration established in Singapore and Malaya
September 12, 1945: Japan formally surrendered Singapore
1946: Singapore became crown colony of Britain
1959: Lee Kuan Yew became prime minister of self-governed Singapore
1971: British military forces completely withdrawn from Singapore

Related Book

Fall of Singapore: 
The Undefeatable British Fortress Conquered

The fall of Singapore is the greatest defeat of the British empire in the Pacific.
​On February 15, 1942, the British surrendered to the Imperial Japanese Army and handed over Singapore and surrounding Malaya countries. The conflict began on December 8, 1941 when Japanese forces bombed Singapore and continued to make their way through the treacherous Malayan jungle. British Prime Minister Winston Churchill stated during the attack, “the worst disaster and the largest capitulation in British history”. Singaporeans were immediately ordered to come in for questioning after the Imperial Japanese Army took over. During the interview, their homes were looted and destroyed by the Kempeitai, the secret Japanese police. 
During the occupation, there were many tragedies. An example is the Sook Ching Massacre. Sook Ching Massacre, literally meaning “purge through cleansing”, began on February 21, 1942. The mass murder of Singapore residents ages 18 to 50, was targeted at eradicating anti-Japanese sentiments. Victims of the massacre were either Chinese, suspected of being pro-Chinese, anti-Japanese, or Communist. Men and women were questioned and if found guilty, they were taken to one of Singapore’s beaches and murdered. The death toll shows less than 5,000 according to the official Japanese record, while Singaporean officials claim the number of victims was at least 50,000.​