On 21 December 1921, The Singapore Free Press and Mercantile Advertiser (1884–1942) reported that the nomination of Mohd Eunos bin Abdullah as a municipal commissioner of Singapore had been approved by then Governor of the Straits Settlements Laurence Nunns Guillemard.



The first election contested by the Workers' Party is the 1957 City Council Election held on 21 December 1957, this was Singapore's first and only election for a wholly elected City Council, in which the young party surprised everyone by winning four out of the five seats it contested. A total of 32 seats were contested. Also up for contention, was the new office of Mayor of Singapore, which would be awarded to the leader of the political party with the majority of seats won. The People’s Action Party (PAP) won 13 of the 14 seats it contested to become the largest party in the new council.



Bedok Swimming Complex was opened to the public on 21 December 1981. Located at 901 New Upper Changi Road, Singapore 467355. There is a Competition Pool, 1 Teaching pool, 1 Wading pool, 1 Learners' pool.




On 21 December 2006 at approximately 15:55 hrs, the Singapore power system experienced a blackout. The blackout affected an estimated 70,000 consumers and about 264 megawatts (MW) of electrical load were shedded in various areas around Singapore. Power was successfully restored to all consumers 45 minutes later at approximately 16:40 hrs. The areas hit by the blackout were mainly residential estates (including Bukit Batok, Choa Chu Kang New Town and Sengkang), with a small number of industrial consumers also affected.