The Federalist Papers were written in the early days of the American Republic to shore up a point of view on the future of the Union. They have quite the pedigree behind them, with their three authors being the first Secretary of the Treasury, Alexander Hamilton; the first Chief Justice of the Supreme Court, John Jay; and the fourth President, James Madison. These three men, who at times had been rivals, banded together to make the case for the ratification of the Constitution and for including certain of their perspectives within it. They shared a pseudonym and set about publishing their work.
What's curious about the Federalist Papers is that their authors didn't actually agree philosophically about certain elements of how the government should work. Hamilton was much more of a centralist, setting up the Federal Reserve Bank. Madison was more of, well, a federalist, believing in a more diffuse power. What they had in common was that they really wanted the Constitution to be ratified and needed to strike back against voices in the press saying it shouldn't be. They also shared the goal of proving that it was possible for humans to govern themselves in a civil and rational manner, without resorting to "accident or force" as the main deciders of our fates. What resulted was 85 essays testifying to the ability of humans to cooperate and choose our shared and individual destinies: the most American idea of them all.
Think you know the ins and outs of the Federalist Papers? Take this quiz to prove your point.