The World's Oldest Constitutions

September 17 marks Constitution Day in the United States and recognizes the adoption of the United States Constitution and those who have become U.S. citizens. September 17, 1787 was the day that the document was signed, before being ratified in 1788 and finally introduced into operation in 1789. As this infographic shows, that makes the U.S. Constitution one of the oldest still in place in the world today.

The United Kingdom has the oldest existing constitution if you count the Magna Carta from 1215. Considered the founding instrument of the constitutional framework of the United Kingdom, two of its articles are still in force today - one of which being: “No free man shall be seized, imprisoned, dispossessed, outlawed, exiled or ruined in any way, nor in any way proceeded against, except by the lawful judgment of his peers and the law of the land."

As illustrated in this chart, based on data from the Comparative Constitution Project, some of the world's oldest democracies have only been around for about 150 years.