Malaysia Day

Malaysia Day (Malay: Hari Malaysia) is a public holiday held on 16 September every year to commemorate the establishment of the Malaysian federation on the same date in 1963. This event saw the union of Malaya, North Borneo (which was renamed Sabah), Sarawak, and Singapore into a single state. Singapore, however, was expelled from the federation less than two years later, on 9 August 1965.

Source by Wikipedia