On September 25, 1789, the First Federal Congress of the United States proposed to the state legislatures twelve amendments to the Constitution. The first two, concerning the number of constituents for each Representative and the compensation of Congressmen, were not ratified.  Articles three through twelve, known as the Bill of Rights, became the first ten amendments to the U.S. Constitution and contained guarantees of essential rights and liberties omitted in the crafting of the original document.  On September 25, 1789, Congress transmitted to the state Legislatures twelve proposed amendments to the Constitution. Numbers three through twelve were adopted by the states to become the United States (U.S.) Bill of Rights, effective December 15, 1791.

http://www.archives.gov/exhibits/charters/bill_of_rights_transcript.html