Signing the Constitution did not make it law. It still had to be approved, state by state, in a fierce campaign that came down to a handful of votes in a few key states.
Ratification is the formal approval that turns a proposed document, a constitution, an amendment, a treaty, into binding law. A text agreed by negotiators means nothing until the proper authority consents to it.
The Constitution set its own high bar: it would take effect only when nine of the thirteen states ratified it through special conventions. The framers deliberately bypassed the state legislatures, taking the question more directly to the people's representatives.
The campaign was a genuine fight. Supporters, the Federalists, and opponents, the Anti-Federalists, battled in print and in the conventions. The Federalist Papers were written precisely to win ratification in the crucial state of New York.
It was often close. Massachusetts, Virginia, and New York ratified only narrowly and only after bitter debate, several of them on the understanding that a bill of rights would follow. The new government rested on those slim margins.
