September 17, 1787
On September 17, 1787 the United States Constitution was signed into law. The U.S. Constitution forms the foundation of our government and guides the laws and politics of American society. Constitution Day was created as a way to both observe the founding of our government and celebrate our citizenship.
America was founded on the following principles – power by the people, limited government, liberty, equality, and justice. These principles all played a major part in the creation of the U.S. Constitution, which is the oldest written constitution that has been in continued use by any country in the world. More information regarding the Constitution, including a transcript, can be found here.