The authors of the Federalist papers presented a masterly defense of the new federal (federalism) system and of the major departments in the proposed central government. They also argued that the existing government under the Articles of Confederation (Confederation, Articles of), the country's first constitution, was defective and that the proposed Constitution would remedy its weaknesses without endangering the liberties of the people.

As a general treatise on republican government, the Federalist papers are distinguished for their comprehensive analysis of the means by which the ideals of justice, the general welfare, and the rights of individuals could be realized. The authors assumed that the primary political motive of man was self-interest and that men—whether acting individually or collectively—were selfish and only imperfectly rational. The establishment of a republican form of government would not of itself provide protection against such characteristics: the representatives of the people might betray their trust; one segment of the population might oppress another; and both the representatives and the public might give way to passion or caprice. The possibility of good government, they argued, lay in man's capacity to devise political institutions that would compensate for deficiencies in both reason and virtue in the ordinary conduct of politics. This theme was predominant in late 18th-century political thought in America and accounts in part for the elaborate system of checks and balances that was devised in the Constitution.

In one of the most notable essays, "Federalist 10," Madison rejected the then common belief that republican government was possible only for small states. He argued that stability, liberty, and justice were more likely to be achieved in a large area with a numerous and heterogeneous population. Although frequently interpreted as an attack on majority rule, the essay is in reality a defense of both social, economic, and cultural pluralism and of a composite majority formed by compromise and conciliation. Decision by such a majority, rather than by a monistic one, would be more likely to accord with the proper ends of government. This distinction between a proper and an improper majority typifies the fundamental philosophy of the Federalist papers; republican institutions, including the principle of majority rule, were not considered good in themselves but were good because they constituted the best means for the pursuit of justice and the preservation of liberty.

All the papers appeared over the signature “Publius,” and the authorship of some of the papers was once a matter of scholarly dispute. However, computer analysis and historical evidence has led nearly all historians to assign authorship in the following manner: Hamilton wrote numbers 1, 6–9, 11–13, 15–17, 21–36, 59–61, and 65–85; Madison, numbers 10, 14, 18–20, 37–58, and 62–63; and Jay, numbers 2–5 and 64.