a. Sikkim was given full statehood in 1975 by 35th constitutional amendment act.

b. Following are the circumstances and events responsible for the merger:

c. Sikkim was ruled by Chogyal rulers of Namgyal dynasty for more than 300 years.

d. Britishers tied up with Sikkim against Nepal, since it was a common enemy to both.

e. Treaty of Titalia was signed between Sikkim and British in 1814 after Anglo Nepal War.

f. But in 1841, the king of Sikkim gave away Darjeeling to British. Britishers started exploiting the state.

g. They did not even pay their annual fee for Darjeeling and in 1861, made Sikkim a protectorate state meaning British shall act as a parent to the state and protect it against the world.

h. Finally, when India got independence, a treaty was signed between Toshi Namgyal (Sikkim ruler) and India to make it an Indian protectorate. In the coming years, the people of Sikkim were not happy with the feudalism and king’s abuse of power.

i. In 1973, Chogyal asked help from the Indian government to control the protestors.

j. A tripartite agreement was signed between Sikkim political parties, king and Indian government.

k. King resisted the decision to restrict his power.

l. In 1975 a referendum was held and more than 90% of the public voted to make Sikkim an Indian state and merge.