It was the Lahore Session of the Indian National Congress at midnight of December 31, 1929 - January 1, 1930, that the Tri-Color Flag was unfurled by the nationalists and a pledge was taken that on January 26 every year, "Republic Day" would be celebrated and that the people would unceasingly strive for the establishment of a Sovereign Democratic Republic India. The professed pledge was successfully redeemed on January 26, 1950, when the Constitution of India framed by the Constituent Assembly of India came into force, although the Independence from the British rule was already achieved on August 15, 1947. It is because of this fact that August 15 is celebrated as Independence Day, while January 26 as Republic Day.
The festivity of Republic Day concludes officially with the intriguing Beating Retreat ceremony on the evening of 29th January. This enthralling ceremony is performed by the military, the Indian Air Force, India Navy and India Army in the Raisina Hills, New Delhi, in front of the President of India as the Chief Guest.