Though the Constitution of India was adopted on 26 November, 1949 by the Constituent Assembly of India it was formally made effective on 26 January, 1950. The reason, it was in 1929 during the Indian National Congress' (INC) Lahore Session that a demand for complete independence from British rule was made in the history of India's freedom struggle. This was followed by a declaration of January 26, 1930 as Purna Swaraj Diwas. To honour this important day in India's freedom movement, our Constitution was adopted on January 26, 1950.
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