As a document defending the longest standing written constitution* in the world, and the one that became the basis of democratic republics worldwide, these articles are among the most important in the last 300 years. This idea is pretty well covered above.
Particularly noteworthy is the relevence to today's American political system which has strayed from the original ideals. For example, in Federalist #10, Madison rails against the modern system of political parties. Check it out.
The Importance of the Union (1-14)
- Federalist #1 -- General Introduction -- Hamilton
- Federalist #2 -- Concerning Dangers from Foreign Force and Influence -- Jay
- Federalist #3 -- Concerning Dangers From Foreign Force and Influence (con't) -- Jay
- Federalist #4 -- Concerning Dangers From Foreign Force and Influence (con't) -- Jay
- Federalist #5 -- Concerning Dangers From Foreign Force and Influence (con't) -- Jay
- Federalist #6 -- Concerning Dangers from Dissensions Between the States -- Hamilton
- Federalist #7 -- Concerning Dangers from Dissensions Between the States (con't) -- Hamilton
- Federalist #8 -- The Consequences of Hostilities Between the States -- Hamilton
- Federalist #9 -- The Union as a Safeguard Against Domestic Faction and Insurrection -- Hamilton
- Federalist #10 -- The Union as a Safeguard Against Domestic Faction and Insurrection (con't) -- Madison
- Federalist #11 -- The Utility of the Union in Respect to Commercial Relations and a Navy -- Hamilton
- Federalist #12 -- The Utility of the Union In Respect to Revenue -- Hamilton
- Federalist #13 -- Advantage of the Union in Respect to Economy in Government -- Hamilton
- Federalist #14 -- Objections to the Proposed Constitution From Extent of Territory Answered -- Madison
Defects of the Articles of Confederation (15-22)
- Federalist #15 -- The Insufficiency of the Present Confederation to Preserve the Union -- Hamilton
- Federalist #16 -- The Insufficiency of the Present Confederation to Preserve the Union (con't) -- Hamilton
- Federalist #17 -- The Insufficiency of the Present Confederation to Preserve the Union (con't) -- Hamilton
- Federalist #18 -- The Insufficiency of the Present Confederation to Preserve the Union (con't) -- Hamilton and Madison
- Federalist #19 -- The Insufficiency of the Present Confederation to Preserve the Union (con't) -- Hamilton and Madison
- Federalist #20 -- The Insufficiency fo the Present Confederation to Preserve the Union (con't) -- Hamilton and Madison
- Federalist #21 -- Other Defects of the Present Confederation -- Hamilton
- Federalist #22 -- Other Defects of the Present Confederation (con't) -- Hamilton
Arguments for the type of Government contained in the Constitution (23-36)
- Federalist #23 -- The Necessity of a Government as Energetic as the One Proposed to the Preservation of the Union -- Hamilton
- Federalist #24 -- The Powers Necessary to the Common Defense Further Considered -- Hamilton
- Federalist #25 -- The Powers Necessary to the Common Defense Further Considered (con't) -- Hamilton
- Federalist #26 -- The Idea of Restraining the Legislative Authority in Regard to the Common Defense Considered -- Hamilton
- Federalist #27 -- The Idea of Restraining the Legislative Authority in Regard to the Common Defense Considered (con't) -- Hamilton
- Federalist #28 -- The Idea of Restraining the Legislative Authority in Regard to the Common Defense Considered (con't) -- Hamilton
- Federalist #29 -- Concerning the Militia -- Hamilton
- Federalist #30 -- Concerning the General Power of Taxation -- Hamilton
- Federalist #31 -- Concerning the General Power of Taxation (con't) -- Hamilton
- Federalist #32 -- Concerning the General Power of Taxation (con't) -- Hamilton
- Federalist #33 -- Concerning the General Power of Taxation (con't) -- Hamilton
- Federalist #34 -- Concerning the General Power of Taxation (con't) -- Hamilton
- Federalist #35 -- Concerning the General Power of Taxation (con't) -- Hamilton
- Federalist #36 -- Concerning the General Power of Taxation (con't) -- Hamilton
The Republican form of Government (37-51)
- Federalist #37 -- Concerning the Difficulties of the Convention in Devising a Proper Form of Government -- Madison
- Federalist #38 -- The Same Subject Continued, and the Incoherence of the Objections to the New Plan Exposed -- Madison
- Federalist #39 -- The Conformity of the Plan to Republican Principles -- Madison
- Federalist #40 -- The Powers of the Convention to Form a Mixed Government Examined and Sustained -- Madison
- Federalist #41 -- General View of the Powers Conferred by The Constitution -- Madison
- Federalist #42 -- The Powers Conferred by the Constitution Further Considered -- Madison
- Federalist #43 -- The Powers Conferred by the Constitution Further Considered (con't) -- Madison
- Federalist #44 -- Restrictions on the Authority of the Several States -- Madison
- Federalist #45 -- The Alleged Danger From the Powers of the Union to the State Governments Considered -- Madison
- Federalist #46 -- The Influence of the State and Federal Governments Compared -- Madison
- Federalist #47 -- The Particular Structure of the New Government and the Distribution of Power Among Its Different Parts -- Madison
- Federalist #48 -- These Departments Should Not Be So Far Separated as to Have No Constitutional Control Over Each Other -- Madison
- Federalist #49 -- Method of Guarding Against the Encroachments of Any One Department of Government
by Appealing to the People Through a Convention -- Hamilton or Madison
- Federalist #50 -- Periodical Appeals to the People Considered -- Hamilton or Madison
- Federalist #51 -- The Structure of the Government Must Furnish the Proper Checks and Balances Between the Different Departments -- Hamilton or Madison
The Legislative Branch (52-66)
- Federalist #52 -- The House of Representatives -- Hamilton or Madison
- Federalist #53 -- The House of Representatives (con't) -- Hamilton or Madison
- Federalist #54 -- The Apportionment of Members Among the States -- Hamilton or Madison
- Federalist #55 -- The Total Number of the House of Representatives -- Hamilton or Madison
- Federalist #56 -- The Total Number of the House of Representatives (con't) -- Hamilton or Madison
- Federalist #57 -- The Alleged Tendency of the New Plan to Elevate the Few at the Expense of the Many Considered in Connection with Representation -- Hamilton or Madison
- Federalist #58 -- Objection That The Number of Members Will Not Be Augmented as the Progress of Population Demands Considered -- Madison
- Federalist #59 -- Concerning the Power of Congress to Regulate the Election of Members -- Hamilton
- Federalist #60 -- Concerning the Power of Congress to Regulate the Election of Members (con't) -- Hamilton
- Federalist #61 -- Concerning the Power of Congress to Regulate the Election of Members (con't) -- Hamilton
- Federalist #62 -- The Senate -- Hamilton or Madison
- Federalist #63 -- The Senate (con't) -- Hamilton or Madison
- Federalist #64 -- The Powers of the Senate -- Jay
- Federalist #65 -- The Powers of the Senate (con't) -- Hamilton
- Federalist #66 -- Objections to the Power of the Senate To Set as a Court for Impeachments Further
Considered -- Hamilton
The Executive Branch (67-77)
- Federalist #67 -- The Executive Department -- Hamilton
- Federalist #68 -- The Mode of Electing the President -- Hamilton
- Federalist #69 -- The Real Character of the Executive -- Hamilton
- Federalist #70 -- The Executive Department Further Considered -- Hamilton
- Federalist #71 -- The Duration in Office of the Executive -- Hamilton
- Federalist #72 -- The Same Subject Continued, and Re-Eligibility of the Executive Considered -- Hamilton
- Federalist #73 -- The Provision For The Support of the Executive, and the Veto Power -- Hamilton
- Federalist #74 -- The Command of the Military and Naval Forces, and the Pardoning Power of the Executive -- Hamilton
- Federalist #75 -- The Treaty-Making Power of the Executive -- Hamilton
- Federalist #76 -- The Appointing Power of the Executive -- Hamilton
- Federalist #77 -- The Appointing Power Continued and Other Powers of the Executive Considered -- Hamilton
The Judicial Branch (78-83)
Conclusions and Miscellaneous Ideas
- Federalist #84 -- Certain General and Miscellaneous Objections to the Constitution Considered and Answered -- Hamilton
- Federalist #85 -- Concluding Remarks -- Hamilton
Cletus the Foetus Pointed out to me that "'longest standing constitution' should be corrected to 'oldest written constitution still in place.' There have been constitutions that were in place for longer, esp. the British unwritten constitution."
*MarkX notes that the Commonwealth of Massachusets' Consitution has been around longer, albeit for only a state