Assembly of Sikkim abolished monarchy and resolved to be a constituent unit of India. A referendum was held on these issues and majority of the voters voted yes. On 15 May 1975 the President of India ratified a constitutional amendment that made Sikkim the 22nd state of India.

State symbols of Sikkim
Song	"Music of Sikkim"
Animal	Red Panda
Bird	Blood Pheasant
Flower	Noble dendrobium (Dendrobium nobile)
Tree	Rhododendron

State symbols
State day	16 May (day of accession to India)
State animal	Red panda
State bird	Blood pheasant
State tree	Rhododendron
State flower	Noble dendrobium (Dendrobium nobile)

Population growth history
Census	Pop.	%±
1951	138,000	—
1961	162,000	17.4%
1971	210,000	29.6%
1981	316,000	50.5%
1991	406,000	28.5%
2001	541,000	33.3%
2011	607,688	12.3%
Sources: Census of India

Sikkim (/ˈsɪkᵻm/) is a northeastern state of India. It borders China in its north and east, Bhutan in its east, Nepal in its west and the Indian state of West Bengal in its south. Sikkim is also located close to the Siliguri Corridor near Bangladesh. Sikkim is the least populous and second smallest among the Indian states. A part of the Eastern Himalaya, Sikkim is notable for its biodiversity, including alpine and subtropical climates, as well as being a host to Kanchenjunga, the highest peak in India and third highest on Earth. Sikkim's capital and largest city is Gangtok. Almost 35% of the state is covered by the Khangchendzonga National Park.

The Kingdom of Sikkim was founded on the Silk Road by the Namgyal dynasty in the 17th century. It was ruled by a Buddhist priest-king known as the Chogyal. It became a princely state of British India in 1890. After 1947, Sikkim continued its protectorate status with the republic of India. It enjoyed the highest literacy rate and per capita income among Himalayan states. In 1975, the Indian military deposed the Sikkimese monarchy. A referendum in 1975 led to Sikkim joining India as its 22nd state.

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