The Constitution of the United States replaced the Articles of Confederation. The Articles of Confederation were the country's first constitution, adopted in 1777, but they created a weak central government that lacked essential powers such as taxation and military authority. Due to these limitations and events like Shays' Rebellion, the Constitutional Convention in 1787 drafted the new Constitution, which established a stronger federal government with three branches: executive, legislative, and judicial. The Constitution came into effect in 1789, officially replacing the Articles of Confederation as the supreme governing document of the United States.