Maryland's ratification made the Articles of Confederation effective.
The Articles were approved by the Continental Congress in 1777 and sent to the states for ratification. Maryland delayed approval because of a dispute over western lands claimed by several states. The state finally ratified the Articles on March 1, 1781, allowing the document to enter into force.
The Articles created the first formal national government of the United States. They established a Congress of the Confederation but gave it limited powers: Congress could conduct diplomacy, make war, and manage western territories, yet it could not directly tax citizens or regulate interstate commerce.
The Articles remained the nation's governing framework until the Constitution replaced them in 1789. A frequent mistake is to say that the Articles were effective when Congress approved them in 1777. Congressional approval was important, but Maryland's final ratification completed the required state process.