Which state constitution, ratified in 1780, is among the world’s oldest still in effect?

The Constitution of Massachusetts, ratified in 1780, is among the world’s oldest written constitutions still in continuous effect.

Massachusetts voters approved the document on June 15, 1780, and it became effective on October 25 of that year. The constitutional convention met in 1779 and 1780 during the Revolutionary War, while Massachusetts was still establishing a permanent state government.

John Adams was the document’s principal author. It contains a declaration of rights and a framework dividing government among executive, legislative, and judicial branches. Its design influenced the United States Constitution, which was drafted seven years later in Philadelphia.

The Massachusetts Constitution is sometimes described as the oldest functioning written constitution in the world, but that wording requires qualification. Parts of San Marino’s constitution and the Magna Carta predate it, while those documents differ in form and historical function. Massachusetts’s constitution is notable for remaining a living governing document, despite later amendments and institutional changes.