Who wrote Federalist No. 10, the famous essay defending a large republic?

James Madison wrote Federalist No. 10, the famous essay defending a large republic.

Published on November 22, 1787, Federalist No. 10 appeared under the shared pseudonym “Publius.” Madison argued that a large republic could help control the harmful effects of factions, which he defined as groups united by interests or passions contrary to the rights of other citizens or the public good.

Madison’s reasoning challenged the common belief that republican government could work only in a small territory. He contended that a larger union would contain more interests and make it harder for one faction to dominate the whole political system. The essay supported ratification of the proposed Constitution, especially in New York.

Federalist No. 10 was one of 85 essays later collected as The Federalist Papers. Madison, Alexander Hamilton, and John Jay wrote the series, but historians identify Madison as the author of numbers 10 and 51. The essay remains one of the most frequently cited explanations of the Constitution’s design.