The United States Constitution was adopted by the Constitutional Convention on September 17, 1787 and became effective when ratified by the ninth state, New Hampshire, on June 21, 1788. The First Amendment to the United States Constitution, which the First Congress approved on September 25, 1789, became effective on December 15, 1791, when ratified by the tenth state, Virginia.

Constitutional concepts regarding religious liberty in America require consideration not only of the First Amendment’s Free Exercise and Establishment Clauses, but also of the Declaration of Independence and Preamble which acknowledge Divine Providence and the Laws of Nature’s God; the three Constitutional provisions regarding solemn truth telling by either religious oaths or secular affirmations as a constitutional accommodation to Quakers, Mennonites, and Jews who had religious scruples against swearing oaths; the Constitutional provision against religious tests for public office; and the Fourteenth Amendment which provided concepts by which the Cantwell and Everson courts applied the First Amendment against state and local governments. The relevant text for each of these provisions are included on this website.