Incorporation of the Bill of Rights is the legal doctrine by which portions of the U.S. Bill of Rights are applied to the states through the Due Process Clause of the Fourteenth Amendment.

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Everson v. Board of Education, 330 U.S. 1 (1947)[1] was the seminal United States Supreme Court case in Establishment Clause law in the United States. In addition to incorporating the Establishment Clause (applying it to the States through the Due Process Clause of the Fourteenth Amendment), Everson was the beginning of a powerful separationist drive by the Court, during which many programs and practices given government sanction were found to have religious purposes or effects and thus invalidated.

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