Head of state second and last incumbent of the office, Yusof bin Ishak, kept the style at 31 August 1963 unilateral declaration of independence and after 16 September 1963 accession to Malaysia as a state (so now as a constituent part of the federation, a non-sovereign level). After its expulsion from Malaysia on 9 August 1965, Singapore became a sovereign Commonwealth republic and installed Yusof bin Ishak as its first President. In 1959 after the resignation of Vice President of Indonesia Mohammad Hatta, President Sukarno abolished the position and title of vice president, assuming the positions of Prime Minister and Head of Cabinet.
Federation in practice highly centralized under the government of the Soviet Union. The Russian Federation has inherited a similar system. Nigeria, Pakistan, India and Malaysia became federations on or shortly before becoming independent from the British Empire. In some recent cases, federations have been instituted as a measure to handle ethnic conflict within a state, such as Bosnia and Herzegovina, and Iraq since 2005. With the United States Constitution having become effective on 4 March 1789, the United States is the oldest surviving federation. On the other end of the timeline is Nepal, which became the newest federation after its constitution