In 1943, the leader of the Indian National Army, Subhas Chandra Bose, rallied for Japanese support to help India be independent of British rule at the Municipal Building.

British prisoners-of-war were rounded up in front of the building to march to POW camps such as Changi Prison and Selarang.

On 12 September 1945, the Imperial Japanese Army official Seishirō Itagaki surrendered to Lord Mountbatten in the building to end World War II in Singapore.

Lee Kuan Yew read out the Malaysia Proclamation at the City Hall in 1963, and declared that Singapore was no longer under British rule.

The ruling People's Action Party abolished the City Council and the Rural Board in 1959, and the mayor's role disappeared.

The City Hall was the place where Prime Minister Goh Chok Tong had his inauguration ceremony and the swearing-in of his cabinet in 1990.