Two and a half years after independence, India formally became a republic when its constitution, the longest in the world, took effect. Dr. Rajendra Prasad was sworn in as the first President in a ceremony at the Government House in New Delhi. The date was chosen deliberately: it marked the tenth anniversary of the 1930 Purna Swaraj declaration, when the Indian National Congress had first demanded complete independence from Britain.
The Constituent Assembly had labored for nearly three years, debating clause by clause under the chairmanship of B.R. Ambedkar, the principal architect of the document and a former 'untouchable' who had risen to become India's chief legal drafter. The result ran to 395 articles and eight schedules, an attempt to weld together a subcontinent of hundreds of languages, religions, and princely states into a single functioning democracy.
On the morning of January 26, 1950, Rajendra Prasad rode in a horse-drawn carriage through New Delhi before being sworn in as President at the Durbar Hall. Guns fired a 31-gun salute, and for the first time an Indian tricolor was unfurled as the flag of a fully sovereign state rather than a dominion still nominally tied to the British Crown.
The date had been chosen with care by the framers: on January 26, 1930, the Indian National Congress had raised its flag and pledged to fight for Purna Swaraj, or complete self-rule. Twenty years later almost to the day, that pledge was fulfilled in law. The anniversary is now celebrated every year as Republic Day, marked by a grand military and cultural parade down Rajpath in New Delhi.