Which document served as the first governing constitution of the United States?

The Articles of Confederation served as the first governing constitution of the United States, established after the American Revolutionary War. Ratified in 1781, it created a system of government that emphasized a decentralized approach, providing limited powers to the national government while granting significant autonomy to the individual states. This was a crucial step in the formation of the new nation, as it outlined the functions and limitations of government powers at the federal level.

The U.S. Constitution came later, ratified in 1788, and replaced the Articles to create a stronger federal government with a balanced system of checks and balances among the branches. The Declaration of Independence, while a seminal document proclaiming the colonies' intent to separate from British rule, did not establish a governing framework. The Magna Carta, on the other hand, is an English document from 1215 that influenced the development of legal and constitutional principles but was not a governing document of the United States. Therefore, the Articles of Confederation is correctly identified as the first governing constitution, as it represented the early attempt to unify the states under a central authority.