Constitution Day is an American holiday celebrated on September 17 to commemorate the day in 1787 when the U.S. Constitution was signed. The Constitution outlines the way the U.S. government works and protects the rights of citizens.
Delegates from 12 of the 13 states met in Philadelphia during the summer of 1787 to modify the Articles of Confederation. The new document they wrote became the U.S. Constitution. Some of the changes included creating the Senate and House of Representatives, establishing the relationship and responsibilities of states to one another and outlining a method by which the Constitution may be modified. Constitution Day recognizes U.S. citizens who have been born in the United States or naturalized.