The oldest written constitution is

The oldest written constitution that is still in effect today is generally considered to be the Constitution of the United States, which was adopted in 1787. While there were written constitutions before the US Constitution, they were not as comprehensive and did not have the same lasting impact. For example, the Constitution of the Commonwealth of Massachusetts, which was adopted in 1780, is considered to be the oldest written constitution of a state in the world, but it has been amended many times since its adoption and has been superseded by the US Constitution in many respects.