Meeting in Philadelphia, delegates approved the final text of Thomas Jefferson's draft, transforming a rebellion into a formal assertion of nationhood. Though most signatures came later, and the vote for independence had actually occurred two days earlier, July 4 became the date printed on the document and forever fixed in American memory as the birth of the United States.
The vote to separate from Britain actually happened on July 2, 1776, but it was July 4 that got stamped on the printed broadsides sent galloping to army camps and town squares, and so July 4 stuck. John Adams, ever prickly about historical accuracy, predicted Americans would celebrate the 2nd with fireworks for generations to come. He was wrong, and he knew it might happen, writing to his wife Abigail with a mixture of pride and mild bitterness.
Jefferson's draft, trimmed and argued over by Congress for days, cut nearly a quarter of his original text, including a passionate condemnation of the slave trade that Southern delegates refused to accept. What remained was still radical: a declaration that governments derive legitimacy from the consent of the governed, and that people possess an inalienable right to overthrow tyranny.
Eerily, both Jefferson and Adams, the document's chief architect and its fiercest advocate, died on the same date, July 4, 1826, exactly fifty years later. Adams's last words reportedly were "Thomas Jefferson survives" — he did not know Jefferson had died hours earlier that same day.