James Madison earned the title Father of the Constitution because of his central role in its drafting and ratification. Throughout the 1780s, Madison was an outspoken critic of the Articles of Confederation and frequently called for the reform or outright rejection of this inadequate governing document. Madison was instrumental in organizing the Philadelphia Convention, which would see a new constitution written.

Before the Philadelphia Convention even began, Madison worked alongside several other delegates from Virginia to put forth a plan that would not just amend the Articles of Confederation but replace them entirely. This became known as the Virginia Plan and would serve as the rough outline of the constitution that would be created.

During the convention itself, Madison was one of the most outspoken in the room. He was often the driving force behind the conversations and arguments made. However, Madison did not bully the other delegates and worked to make sure that everyone's concerns were voiced.

Madison was also instrumental in calling for the passage of a Bill of Rights. He believed that the specific enumeration of individual rights was paramount to the survival of the newly adopted Constitution. Madison was personally responsible for drafting the first ten amendments that became the Bill of Rights and gathering a broad coalition in Congress to ratify them.

For all this, James Madison has frequently been referred to as the Father of the Constitution.