The formation of the new federation was planned to occur on 1 June 1963, but was later postponed to 31 August 1963, to coincide with the sixth Hari Merdeka. Several issues related to objections of neighbouring Indonesia and the Philippines to the formation of Malaysia delayed the declaration to 16 September of the same year. The postponement was also done to allow the United Nations team time to conduct fact-finding mission in North Borneo and Sarawak regarding the two states participation in a new federation. Contrary to popular beliefs, no referendum was ever conducted in both North Borneo and Sarawak; Singapore held a referendum on 1 September 1962, with all three options endorsing integration into Malaysia. The formation of Malaysia was made possible with the signing of the international treaty the Malaysia Agreement 1963 between the United Kingdom, the Federation of Malaya ; Sarawak, North Borneo and Singapore of the remaining component States. The Malaysia Agreement 1963 set out the terms and conditions for the component States to be federated under a new constitution into one new nation called Malaysia. It is under this Agreement that the "Malaysia Bill",, the constitutions of Sarawak, Sabah and Singapore were created by agreement of all the parties. The Malaysia Bill was introduced in the Malayan Parliament on 9 July 1963, and received consent from Tuanku Syed Putra, the Yang di-Pertuan Agong, on 29 August 1963. Prior to the formation of Malaysia, Sarawak gained its Self-Government Administration on 22 July 1963, while North Borneo began Self-Government Administration from the United Kingdom on 31 August 1963, thus coinciding with the sixth anniversary of the Malayan independence. Prior to 2010, Malaysia Day was observed as a state public holiday in Sabah and Sarawak. Since 2010, Malaysia Day has been a nationwide public holiday. Prime MinisterNajib Razak made the decision after a question-and-answer session at Parliament on 19 October 2009, giving Malaysians two celebrations related to the country's independence. In conjunction with the day celebration in 2018 under the new Pakatan Harapan government, Prime Minister Mahathir Mohamad has promised to restore Sabah and Sarawak status in the Malaysian federation in accordance with the Malaysia Agreement, changing "their status from merely a state to an equal partner of the Malayan states".
was a song composed by Bobby Gimby to celebrate the Formation of Malaysia on 16 September 1963. Bobby Gimby received the nickname "The Pied Piper of Canada" after the Prime Minister nicked Gimby as "the Pied Piper from Canada". The song was recorded in Kuala Lumpur and Singapore. It is a folk song with a length of 2 minutes sung by the Choir of the Marymount Vocational School. On the days before the merger, it was taught to school children prior to merger and became an instant hit when it was broadcast over the air-waves of all parts of Malaysia.
