The Federalist Papers were a series of 85 essays written by Alexander Hamilton, John Jay, and James Madison between October 1787 and May 1788. The essays were published anonymously, under the pen name "Publius," in various New York state newspapers of the time. The primary purpose of The Federalist Papers was to urge New Yorkers to ratify the proposed United States Constitution, which was drafted in Philadelphia in the summer of 1787. The essays explained particular provisions of the Constitution in detail and lobbied for its adoption over the existing Articles of Confederation. The Federalist Papers are often used today to help interpret the intentions of those drafting the Constitution, as Hamilton and Madison were each members of the Constitutional Convention. The essays were aimed at convincing opponents of the US Constitution to ratify it so that the new federal system could be established. The Federalist Papers are considered one of the most significant American contributions to the field of political philosophy and theory and are still widely considered to be the most authoritative source for determining the original intent of the framers of the US Constitution.