The Bill of Rights may well be the most celebrated part of the Constitution of the United States, the home to long-cherished guarantees of Americans' most fundamental rights and freedoms. Freedom of speech. Freedom of religion. Freedom of the press. The right to bear arms. Freedom from imprisonment without a fair trial. And so on.
But the Bill of Rights wasn't even included in the original document signed in Philadelphia in the summer of 1787. Many of the Framers of the Constitution—James Madison foremost among them—originally believed that no Bill of Rights was necessary, that the structure of limited government (with its internal checks and balances) created by the Constitution would ensure that individuals' liberties would always be protected. But as the debate unfolded over whether or not to ratify the Constitution, many Americans began to see an official Bill of Rights as more and more important. Five states (including powerful and populous Massachusetts, New York, and Virginia) all agreed to ratify the Constitution only on the condition that their delegations to the new Congress immediately seek to create a Bill of Rights.
The first Congress passed 12 proposed amendments to the Constitution in 1789; ten of those, the ten now known as the Bill of Rights, were ratified and went into effect in 1791.
Check out Shmoop's detailed analysis of the full text of each of the ten amendments that make up the Bill of Rights below: