What is the Declaration of Independence you might wonder?
American Independence Day is celebrated on the Fourth of July every year. July 4th, 1776, was a day that represented the Declaration of Independence and the birth of the United States of America as an independent nation.
But July 4, 1776 wasn't the day that the Continental Congress decided to declare independence (they did that on July 2, 1776).
It wasn’t the day the American Revolution started either (that had happened back in April 1775).
And it wasn't the day Thomas Jefferson wrote the first draft of the Declaration of Independence (that was in June 1776). Or the date on which the Declaration was delivered to Great Britain (that didn't happen until November 1776). Or the date it was signed (that was August 2, 1776).
So what did happen on July 4, 1776?
The Continental Congress approved the final wording of the Declaration of Independence on July 4, 1776. They'd been working on it for a couple of days after the draft was submitted on July 2nd and finally agreed on all of the edits and changes.
July 4, 1776, became the date that was included on the Declaration of Independence, and the fancy handwritten copy that was signed in August (the copy now displayed at the National Archives in Washington, D.C.) It’s also the date that was printed on the Dunlap Broadsides, the original printed copies of the Declaration that were circulated throughout the new nation. So when people thought of the Declaration of Independence, July 4, 1776 was the date they remembered.
In contrast, Constitution Day is celebrated on September 17th of each year, as the anniversary of the date the Constitution was signed, not the anniversary of the date it was approved.