In 1975, the Prime Minister of Sikkim appealed to the Indian Parliament for Sikkim to become a state of India. In April of that year, the Indian Army took over the city of Gangtok and disarmed the Chogyal's palace guards. Thereafter, a referendum was held in which 97.5% of voters supported abolishing the monarchy, effectively approving union with India. On 16 May 1975, Sikkim became the 22nd state of the Indian Union, and the monarchy was abolished. To enable the incorporation of the new state, the Indian Parliament amended the Indian Constitution. First, the 35th Amendment laid down a set of conditions that made Sikkim an "Associate State," a special designation not used by any other state. Later, the 36th Amendment repealed the 35th Amendment, and made Sikkim a full state, adding its name to the First Schedule of the Constitution.
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