Today is Bill of Rights Day, memoration first established byPresident Franklin D. Rooseveltto cherish the ‘immeasurable privileges which the charter guaranteed’ and to rededicate its principles and practice.”

Here are five facts you should know about the Bill of Rights:

1. At the Constitutional Convention in 1787, George Mason of Virginia said that he “wished the plan had been prefaced by a Bill of Rights,” because it would “give great quiet” to the people. A motion was made that mittee be established to prepare a Bill of Rights, but the delegates, voting as states, defeated it 10-0. The reason? It was deemed to be unnecessary. (Some were also skeptical about what James Madison called “parchment barriers” against “overbearing majorities.”)

2. James Madison initially presented 19 amendments for ratification, but the House only advanced 17 of them. The Senate trimmed it further to 12 before sending them to the states. In the end, numbers three through 12 were approved and collectively became our Bill of Rights on December 15, 1791.

3. The U.S. Bill of Rights was heavily influenced by George Mason’s Virginia Declaration of Rights (1776), the English Bill of Rights (1689), and the Magna Carta (1215).

4. The third amendment (No Soldier shall, in time of peace be quartered in any house, without the consent of the Owner, nor in time of war, but in a manner to be prescribed by law.) is the least contested amendment in the Bill of Rights. To date, no significant Supreme Court case hinges on the amendment. One of the most prominent citations, notes Andrew P. Morriss, is in the “name of marital privacy as support for constitutional restrictions on state government’s abilities to regulate the sale of contraceptives in Griswold v. Connecticut (1965).”

5. Three states—Connecticut, Georgia, and Massachusetts—didn’t ratify the bill of rights until 1939, the sesquicentennial anniversary of the Constitution.