In the United States, Independence Day, commonly known as the Fourth of July, is a federal holiday commemorating the adoption of the Declaration of Independence on July 4, 1776, declaring independence from the Kingdom of Great Britain.

The Declaration of Independence was unanimously declared by the thirteen United States of America. It was adopted by the Continental Congress in Philadelphia on July 4, 1776. The task of getting the document signed began on August 2, 1776. Congress had to ensure that all states would have access to an authenticated copy of the Declaration and did so by ordering a special printing of multiple copies on January 18, 1777.

Although celebrated upon publication, the Declaration was initially neglected following the American Revolution.

Its symbolic stature grew over the years, most notably through the influence of Abraham Lincoln, who viewed the Declaration as an ideal for which the nation should strive, especially as expressed in Jefferson's famous preamble:

'We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.'

In 1776 in Philadelphia the Declaration of Independence was read publicly on July 8. In Williamsburg, a celebration occurred on July 25. Trenton, NJ proclaimed its independence with a gathering of the militia and citizens: "The declaration, and other proceedings, were received with loud acclamations" 26 July. In New York, the "Declaration of Independence was read at the head of each brigade of the continental army posted at and near New York, and every where received with loud huzzas and the utmost demonstrations of joy."

The following is a description of the event as printed in a local newspaper in 1777:

Yesterday the 4th of July, being the Anniversary of the Independence of the United States of America, was celebrated in this city with demonstration of joy and festivity. About noon all the armed ships and gallies in the river were drawn up before the city, dressed in the gayest manner, with the colours of the United States and streamers displayed. At one o'clock, the yards being properly manned, they began the celebration of the day by a discharge of thirteen cannon from each of the ships, and one from each of the thirteen gallies, in honour of the Thirteen United States. In the afternoon an elegant dinner was prepared for Congress, to which were invited the President and Supreme Executive Council, and Speaker of the Assembly of this State, the General Officers and Colonels of the army, and strangers of eminence, and the members of the several Continental Boards in town. The Hessian band of music taken in Trenton the 26th of December last, attended and heightened the festivity with some fine performances suited to the joyous occasion, while a corps of British deserters, taken into the service of the continent by the State of Georgia, being drawn up before the door, filled up the intervals with feux de joie. After dinner a number of toasts were drank, all breaking independence, and a generous love of liberty, and commemorating the memories of those brave and worthy patriots who gallantly exposed their lives, and fell gloriously in defence of freedom and the righteous cause of their country. Each toasts was followed by a discharge of artillery and small arms, and a suitable piece of music by the Hessian band. The glorious fourth of July was reiterated three times accompanied with triple discharges of cannon and small arms, and loud huzzas that resounded from street to street through the city. Towards evening several troops of horse, a corps of artillery, and a brigade of North Carolina forces, which was in town on its way to join the grand army, were drawn up in Second street and reviewed by Congress and the General Officers. The evening was closed with the ringing of bells, and at night there was a grand exhibition of fireworks, which began and concluded with thirteen rockets on the commons, and the city was beautifully illuminated. Every thing was conducted with the greatest order and decorum, and the face of joy and gladness was universal. Thus may the 4th of July, that glorious and ever memorable day, be celebrated through America, by the sons of freedom, from age to age till time shall be no more. Amen, and amen (Virginia Gazette, 18 July 1777).

The original handwritten copy of the Declaration of Independence has not survived.

On July 19, 1776 Congress ordered a copy be "engrossed" (hand written in fair script on parchment by an expert penman) for the delegates to sign.

The first and most famous signature on the engrossed copy was that of John Hancock, President of the Continental Congress. Two future presidents, Thomas Jefferson and John Adams, were among the signatories. Edward Rutledge (age 26), was the youngest signer, and Benjamin Franklin (age 70) was the oldest signer. The fifty-six signers of the Declaration represented the new states as follows (from North to South):

New Hampshire: Josiah Bartlett, William Whipple, Matthew Thornton

Massachusetts: Samuel Adams, John Adams, John Hancock, Robert Treat Paine, Elbridge Gerry

Rhode Island: Stephen Hopkins, William Ellery

Connecticut: Roger Sherman, Samuel Huntington, William Williams, Oliver Wolcott

New York: William Floyd, Philip Livingston, Francis Lewis, Lewis Morris

New Jersey: Richard Stockton, John Witherspoon, Francis Hopkinson, John Hart, Abraham Clark

Pennsylvania: Robert Morris, Benjamin Rush, Benjamin Franklin, John Morton, George Clymer, James Smith, George Taylor, James Wilson, George Ross

Delaware: George Read, Caesar Rodney, Thomas McKean

Maryland: Samuel Chase, William Paca, Thomas Stone, Charles Carroll of Carrollton

Virginia: George Wythe, Richard Henry Lee, Thomas Jefferson, Benjamin Harrison, Thomas Nelson, Jr., Francis Lightfoot Lee, Carter Braxton

North Carolina: William Hooper, Joseph Hewes, John Penn

South Carolina: Edward Rutledge, Thomas Heyward, Jr., Thomas Lynch, Jr., Arthur Middleton

Georgia: Button Gwinnett, Lyman Hall, George Walton