What is the main purpose of the Federalist Papers?

The main purpose of the Federalist Papers was indeed to defend the Constitution and outline its principles. Authored primarily by Alexander Hamilton, James Madison, and John Jay, these essays were written to persuade the public and state legislatures to support the ratification of the United States Constitution after it was drafted in 1787. The papers articulate the philosophy behind the Constitution, discussing the necessity of a strong federal government while addressing concerns about potential abuses of power. By providing detailed arguments in favor of the proposed framework of government, the authors aimed to reassure skeptics and highlight the advantages of the new Constitution, thus clearly establishing the Federalist Papers as a pivotal contribution to American political thought and governance.

The other choices do not capture the primary focus of the Federalist Papers. Promoting political parties and serving as a guide to European affairs are not central themes in their writings. Additionally, while the Bill of Rights is an important part of U.S. history, it was addressed after the Constitution was ratified, and the Federalist Papers do not specifically outline its framework.