An image of the title page to a collection of The Federalist Papers published in book form in 1799. After the Constitutional Convention of 1787 the proposed Constitution was sent to the states to be ratified. During this time the proponents of the Constitution were known as Federalists and the opponents Anti-Federalists. Both groups were prolific in defense of their positions. John Jay, Alexander Hamilton and James Madison published a number of essays in New York newspapers under the pen name "Publius." The essays were later published in book form and are known as "The Federalist Papers."