Tripura was formed as a state of India.

On October 15, 1949, Tripura was integrated into the Indian Union as a princely state.

The merger agreement was signed by the ruler of Tripura and representatives of the Government of India.

On January 21, 1972, Tripura, Meghalaya, and Manipur became full-fledged states of India under the North-Eastern Areas (Reorganisation) Act, 1971.

Every year on January 21, Tripura celebrates its Formation Day.
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