The architect of the Indian Constitution was Dr B R Ambedkar.

Dr Bhimrao Ramji Ambedkar, popularly known as Babasaheb Ambedkar, was a prominent Indian jurist, economist, social reformer, and politician. He played a pivotal role in drafting and formulating the Constitution of India, which was adopted on 26th November 1949 and came into effect on 26th January 1950.

Dr Ambedkar's contribution to the Constitution can be understood by examining his role in various aspects:

1. Chairman of the Drafting Committee:
- Dr Ambedkar was appointed as the Chairman of the Drafting Committee of the Constituent Assembly in 1947.
- As the Chairman, he led the committee responsible for drafting the Constitution of India.
- He played a crucial role in ensuring that the Constitution reflected the principles of justice, equality, and social reform.

2. Vision for a Progressive Constitution:
- Dr Ambedkar envisioned a Constitution that would guarantee fundamental rights, social justice, and equality for all citizens.
- He advocated for the inclusion of provisions such as abolition of untouchability, reservation for disadvantaged communities, and protection of civil liberties.
- His vision aimed to uplift marginalized sections of society and create a fair and inclusive democratic framework.

3. Influence of his Intellectual Background:
- Dr Ambedkar's extensive knowledge and experience in law, economics, and social issues greatly influenced the content of the Constitution.
- His understanding of the challenges faced by oppressed communities and his commitment to their empowerment shaped the provisions related to reservations, protection of minority rights, and affirmative action.

4. Incorporation of Fundamental Rights and Directive Principles:
- Dr Ambedkar played a significant role in ensuring the inclusion of fundamental rights in the Constitution.
- He emphasized the importance of protecting individual liberties and ensuring social justice.
- He also contributed to the formulation of Directive Principles of State Policy, which provide guidelines for the government to work towards creating a just and equitable society.

5. Advocate for Social Equality:
- Dr Ambedkar was a strong advocate for social equality and fought against caste-based discrimination.
- He played a crucial role in the inclusion of provisions against untouchability and the promotion of social reforms in the Constitution.
- His efforts were instrumental in ensuring that the Constitution addressed the historical injustices faced by marginalized communities.

In conclusion, Dr B R Ambedkar's contributions as the architect of the Indian Constitution were significant. His vision for a progressive and inclusive society, combined with his expertise and commitment to social justice, shaped the foundational document of independent India. His contributions continue to impact the lives of millions of Indians, making him one of the most important figures in the history of Indian democracy.