The United States Bill of Rights consists of the first 10 amendments to the Constitution.
James Madison introduced a package of proposed amendments in Congress in 1789, responding partly to concerns raised by Anti-Federalists during the Constitution's ratification debate. Congress initially sent 12 proposed articles to the states rather than 10.
The states ratified Articles Three through Twelve on December 15, 1791. Those ten articles became Amendments One through Ten. The original proposed Article Two was eventually ratified in 1992 as the Twenty-seventh Amendment, while the original Article One remains unratified. This history explains why the Bill of Rights contains 10 amendments even though Congress originally proposed 12 articles.
The amendments protect or address rights and principles including religious freedom, speech, press, assembly, due process, jury trials, and limits on excessive punishment. They were added to the Constitution rather than replacing its original articles.