You may or may not have heard of this one.
This is the document in which the 13 colonies formally declared their independence from Britain Congress voted to accept the Declaration on July 4, 1776 - celebrated today as Independence Day in the United States. Contrary to popular belief, the document wasn't actually signed on July 4 - the first signatures weren't added until the Declaration was formally transcribed, sometime around the beginning of August - others were added as the delegates arrived in Philadelphia. By some accounts the final signature wasn't added until sometime in 1777.
The Declaration, with its statement that "All men are created equal" and that they had the right to "Life, Liberty and the pursuit of happiness" became an inspiration for other revolutions that came after it. Most notably the French Revolution - against the very government that supported the Americans in their bid for Independence. Oops.