America declared independence on July 2. Here's why the 4th is celebrated as a holiday.

The Fourth of July is a quintessential holiday in the United States, commemorating the Declaration of Independence. Celebrating with family barbeques, hot dogs, parades, fireworks and the red, white and blue is a crucial part of the holiday. But did you know the anniversary of American independence is July 2, not July 4? Twelve of the thirteen American colonies had already approved the resolution by July 2, 1776, but the document declaring independence from Great Britain wasn’t officially adopted until July 4, reports USA TODAY. The historic document explained why the American colonies wished to sever ties with Great Britain.

According to Constitution Center, the Continental Congress declared its freedom from Great Britain on July 2, 1776, when it voted to approve a resolution submitted by delegate Richard Henry Lee of Virginia, declaring “That these United Colonies are, and of right ought to be, free and independent States, that they are absolved from all allegiance to the British Crown, and that all political connection between them and the State of Great Britain is, and ought to be, totally dissolved.”

John Adams even wrote to his daughter, predicting that July 2 would be marked as a national holiday for generations to come. “[Independence Day] will be the most memorable epoch, in the history of America. I am apt to believe that it will be celebrated, by succeeding Generations, as the great anniversary festival... It ought to be solemnized with pomp and parade with shows, games, sports, guns, bells, bonfires and illuminations from one end of this continent to the other from this time forward forever more,” Adams wrote.

While independence was voted on July 2, it needed to be explained to the public via a document, which was proposed in draft form by the Committee of Five (John Adams, Roger Sherman, Robert Livingston, Benjamin Franklin and Thomas Jefferson). It took two days for the Congress to agree to the edits.

Debates over slavery postponed the formal adoption of the Declaration of Independence. According to National Geographic, there was a heated discussion about slavery in a passage in which Jefferson accused King George III of violating the lives and liberty of “a distant people who never offended him, captivating and carrying them into slavery in another hemisphere, or to incur miserable death in their transportation thither.” 

In another, he accused the king of encouraging enslaved people to escape and join the British forces. Instead of abolishing slavery as most delegates personally profited from the labor of slaves, Congress took out the controversial passage. Finally, the Continental Congress voted to adopt the Declaration of Independence on July 4, 1776. The celebrations truly became widespread only after the War of 1812. On June 28, 1870, Congress passed a bill making Independence Day a federal holiday, and in 1941, it was amended to make it a paid holiday for federal employees.