From the Heritage Foundation:
James Madison is generally regarded as the father of the United States Constitution. No other delegate was better prepared for the Federal Convention of 1787, and no one contributed more than Madison to shaping the ideas and contours of the document or to explaining its meaning.
In 1787 and 1788, Madison authored, with Alexander Hamilton and John Jay, the Federalist Papers, a penetrating commentary on the principles and processes of the proposed Constitution. In 1789, as a member and leading voice in the House of Representatives in the new Republic, Madison introduced a series of constitutional amendments that would form the basis of the Bill of Rights. A few years later, he and Thomas Jefferson organized the opposition to Alexander Hamilton’s administrative policies, thereby founding the first political party in America.
Winston Churchill once said that a man must choose either a life of words or a life of action. Like Churchill, Madison demonstrated that rare individuals could be both scholars and statesmen. His scholarly quest to discover the means by which popular government could also be just government was not merely academic; his dedication to finding a “republican remedy” to the problems that had always plagued popular government was meant to answer the “sighs of humanity” throughout the ages.
Madison believed that he and his generation of American Founders had discovered the way to rescue popular government from its past failures, but that its ultimate success depended on the great experiment in self-government entrusted to the hands of future generations. The destiny of republican government, Madison believed, is staked on the vigilance of the American people to tend “the sacred fire of liberty.”