(CNN)Here's a look at United States Constitution, which establishes and sets forth the ultimate law of the land.
May 25, 1787 - The Constitutional Convention meets in Philadelphia to discuss revising the Articles of Confederation. They decide instead to write the Constitution of the United States, and hold secret meetings with sentries posted outside the doors.
The promise of a Bill of Rights helped the Constitution get ratified in several important states.
An amendment may be proposed by two-thirds of each house of Congress, or by a national convention called by Congress in response to requests by two-thirds of the state legislatures.
Amendment 1 - Freedom of religion, speech, and the press; rights of assembly and petition - proposed September 25, 1789; ratified December 15, 1791