Answer: “Publius” was the pseudonym used by the authors of the collection of essays that became known as “The Federalist Papers”: Alexander Hamilton, James Madison and John Jay.
The first essay was published on October 27, 1787.
Title page of the first collection of The Federalist Papers (1788- CREDIT: Library of Congress The Federalist (vol. 1) J and A M’Lean, publisher, New York, 1788. From Rare Books and Special Collections Division in Madison’s Treasures
“The Federalist Papers were written and published to urge New Yorkers to ratify the proposed United States Constitution, which was drafted in Philadelphia in the summer of 1787. In lobbying for adoption of the Constitution over the existing Articles of Confederation, the essays explain particular provisions of the Constitution in detail. For this reason, and because Hamilton and Madison were each members of the Constitutional Convention, the Federalist Papers are often used today to help interpret the intentions of those drafting the Constitution.”
Source: Library of Congress Complete Text of The Federalist Papers
Following ratification of the Constitution and the establishment of the new federal government, Hamilton became first secretary of the Treasury under George Washington, Madison remained in Congress where he drafted the Bill of Rights — and later became the 4th president– and Jay became the first Chief Justice of the Supreme Court.
