The United States Bill of Rights became the first ten amendments to the Constitution when those amendments were ratified in 1791. It protects liberties including speech, religion, press, assembly, and due process.
James Madison introduced the amendments in Congress after studying objections raised by Anti-Federalists during the ratification debate. Congress originally proposed twelve articles on September 25, 1789. The states ratified Articles Three through Twelve on December 15, 1791, and those became Amendments One through Ten.
The two proposed articles that came first in the 1789 list did not initially become part of the Constitution. One concerned congressional apportionment and remains unratified; the other, dealing with congressional pay, was eventually ratified in 1992 as the Twenty-seventh Amendment. Thus, the Bill of Rights is the first ten amendments, not all twelve originally proposed by Congress.