The sources used to create the constitution were many.
The Government of India Act of 1858, the Indian Councils Acts of 1861, 1892, and 1909, the Government of India Acts of 1919 and 1935, and the Indian Independence Act of 1947 were among the laws whose important provisions were incorporated in our present constitution with some modifications
Keeping in mind the needs and circumstances of India.
The Indian Constitution was also an outcome of an amalgamation of several constitutional principles, borrowed from the constitutions of many countries and adapted according to the needs of the diverse Indian society accordingly in consonance with the principles of democracy, equality, social justice.
Constitution of the United States of America
Fundamental Rights
Federal Structure of Government
Electoral College
Independence of the Judiciary and separation of powers among the three branches of the Government
Judicial Review
President as the Supreme Commander of Armed Forces
Equal Protection Under Law
British Constitution
Parliamentary Government
Single Citizenship
Rule of law
Writs
Speaker and his/her role
Law Making Procedure
Procedure established by Law
Canadian Constitution
A Quasi-Federal form of government, with the following features —
A Federal Structure with a Centre
Distribution of powers between the Central Government and state governments
Residual Powers retained by the Central Government
Irish Constitution
Directive Principles of State Policy
Nomination of members to Rajya Sabha (Upper House)
Method of Election of President
French Constitution
The ideals of Liberty, Equality and Fraternity
Australian Constitution
Freedom of trade and commerce within the country and between the states
Power of the National Legislature to make laws for implementing treaties, even on matters outside normal Federal Jurisdiction
Concurrent List
Constitution of the Soviet Union (USSR) Fundamental Duties under Article 51-A
A Constitutionally mandated Planning Commission
Constitution of South Africa
Procedure for Amendment
Election of Rajya Sabha (Upper House) members
Constitution of Germany
Emergency Provisions
Constitution of Japan
Procedure Established by Law