The Articles of Confederation served as the first governing document of the United States. Although the document was completed in 1777, the Articles did not go into effect until March 1, 1781, when all of the 13 states had finally completed their ratification of them. Since the Articles of Confederation were replaced by the US Constitution on March 4, 1789, the Articles were implemented for only eight years. During this time, they were for the most part unsuccessful in giving the United States an effective government for a number of reasons.
First of all, the individual states were fearful of losing their autonomy, and so they did not create a strong enough central government. Whereas the US Constitution provides for three branches of government—the executive branch, the judicial branch, and the legislative branch—the Articles of Confederation only mentioned Congress, which is the legislative branch. There was no executive branch to enforce the laws that Congress passed and no national court system to interpret the laws. These two branches, along with Congress, create an effective system of checks and balances in government.
Additionally, Congress did not have the power to effectively govern. It could not raise taxes or regulate commerce. Much confusion was caused by the individual states maintaining their own military units, regulating interstate trade, negotiating with foreign governments, and even printing their own money.
In short, the Articles of Confederation brought the states together in a "league of friendship," but they did not give sufficient power to the central government to effectively build and govern a new nation. Each state had one vote in Congress, so the more populated states felt poorly represented. Since Congress could not raise taxes but only request money from the states, it could not pay back the government's debts after the Revolutionary War. All of these problems led the founding fathers to draft a new Constitution that would meet the needs of the new nation.