I think every age has some major issue that people understand as a kind of agenda for that generation, a major problem that is to be resolved. In the 18th century, clearly, it was the problem of government. How could you design a government, a new government that didn't have kings, didn't have hereditary rule, that could function, that could be stable? Republics of the past had been characteristically short-lived. The great republics were gone. What had happened to Rome? What about the English Commonwealth? What had happened to Greece?

—Pauline Maier, Scholar

The Founding Fathers, in general, and James Madison, in particular, were dedicated students of past governments. When Madison arrived in Philadelphia for the Constitutional Convention in May, 1787, he came armed with dense notebooks fill with his reflections on ancient republics, well-known and obscure.

Madison had become convinced through his studies that what was generally viewed as the chief impediment to creating a unified republic in America—its sheer size and countless regional and individual interests—could become, by way of a series of checks and balances, the central means to protect those interests and thus hold the union together.

Madison was an unlikely giant at the Constitutional Convention. He was a small man with a shy manner, not given to thunderous speeches. But he had vast intellectual gifts and his well-reasoned, well-supported arguments played a huge role in framing the constitution. Both at the convention and afterward, during the ratification process, his influence was enormous.