Why does the United States of America celebrate Independence Day on 4 July?

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But 2 July is not the day that Americans celebrate every year. They chose instead 4 July, two days later, when Congressmen signed the finished version of the Declaration of Independence – a document that would announce their decision to the world.

Drafted mostly by Thomas Jefferson, a prominent lawyer and planter from Virginia (and later the third president of the United States between 1801–09), the Declaration of Independence features the famous lines: “We hold these truths to be self-evident, that all men are created equal” and have “certain unalienable rights” – among them “life, liberty, and the pursuit of happiness”. The declaration also describes Native Americans as “merciless savages”and blames King George for inciting American slaves to insurrection.

More than 240 years later, Americans still celebrate the day their rebel leaders put their signatures to Jefferson’s words.

Here are five things you might not know about the history of Independence Day celebrations…

The Declaration of Independence is a sacred document in the United States

Not for nothing did the late historian Pauline Maier call her 1997 book about the declaration, American Scripture.

Yet the document itself wasn’t always treated well; it barely survived the British burning of Washington DC in 1814. But during the Second World War, the Declaration of Independence was delivered to Fort Knox, Kentucky, under Secret Service protection. In 1952, the declaration was placed in aspecially designed, bullet-proof case in a “shrine” under the rotunda of the National Archives in Washington DC. At night, it is lowered into a concrete and steel-reinforced bunker. And every day, Americans file past and stare at it in reverence.

There’s a share of the divine in the declaration’s text, too. Jefferson wasn’t known as the most pious Christian, but he included “nature’s god” in his text – by whose power “all men are created equal”. He also closed the text by invoking its signers’ “sacred honor” along with their lives and fortunes, which the American revolutionaries were putting on the line when they broke away from Great Britain.

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The Declaration of Independence has had many imitators, at home and abroad

The events of 4 July 1776 helped inspire colonial independence movements around the world – especially in South America, where revolution overthrew the Spanish empire in the first decades of the 19th century.

Venezuela’s 1811 declaration of independence, for example, had clear echoes of Jefferson’s text, announcing that the provinces of Venezuela “are, and ought to be […] free, sovereign, and independent states.” Revolutionaries across the continent and elsewhere drew on the American example, as they asserted their right to self-government against European empires.

In the United States itself, the declaration has also found many echoes in later political documents. “That all men are created equal”, wrote the abolitionist William Lloyd Garrison in his own 1833 declaration, was “the corner-stone” of America’s “temple of freedom”.

Women’s rights activists, too, used the declaration’s words to promote their causeand to highlight inconsistencies in the United States’ implementation of freedom. “The history of mankind,” it was declared at the Seneca Falls Convention of 1848, “is a history of repeated injuries and usurpations on the part of man toward woman.”

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Jeremy Bentham was not impressed by the declaration’s logic

Not many critics of independence responded directly to the ideas expressed in the Declaration of Independence, but the late 18th/early 19th-century British philosopher Jeremy Bentham certainly did. The utilitarian and future designer of the panopticon [a type of institutional building which represented a system of control] was thoroughly unconvinced by the logic of Jefferson and his co-authors. For one thing, if the “right to life, liberty, and happiness” was so “unalienable”, he asked, then what had justified the American invasion of Canada in 1775, with all the death and misery it caused?

Bentham wasn’t a fan of the philosophy of natural rights, either: he called the French Declaration of the Rights of Man in 1789 “nonsense upon stilts”. When the Americans declared an unalienable right to liberty, he wondered if that meant “thieves are not to be restrained from theft, murderers from murder”. He wasn’t sure about all men being created equal, either. Wouldn’t that mean babies had the same power as full-grown adults? Pure mumbo-jumbo, Bentham reckoned – not to mention a threat to government of any kind.

Frederick Douglass attacked the declaration’s hypocrisies

The British weren’t the only ones to find fault with the Declaration of Independence. Frederick Douglass had escaped slavery as a young man and turned himself into a leader of the abolition movement, when he was asked to speak at an Independence Day celebration in 1852. With President Millard Fillmore in the audience, Douglass proceeded to denounce the hypocrisy of a nation that proclaimed “all men are created equal” while treating more than 10 per cent of its population as slaves.

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“Could I reach the nation’s ear,” stormed Douglass, “I would today pour out a fiery stream of biting ridicule, blasting reproach, withering sarcasm, and stern rebuke… the hypocrisy of the nation must be exposed; and its crimes against God and man must be proclaimed and denounced.”

Today, too, institutional racism and other forms of systematic inequality may seem to undermine the claims of Jefferson’s visionary preamble. Perhaps the Fourth of July will become a moment to remember the promises left unfulfilled, as well as the achievements of American liberty.

• Read more | Lincoln and slavery: "If I could save the union without freeing any slave, I would"

Now every Fourth of July, Monticello welcomes new citizens

Independence Day is celebrated in all sorts of ways across the United States – many of them involving barbeque, beer, and a healthy dose of patriotic red, white and blue.

At Jefferson’s mountaintop home in Virginia – Monticello – they have a special tradition of their own. For more than 50 years now they’ve held a naturalisation ceremony on Independence Day, admitting people from all over the world to become citizens of the United States.

When the nation came into being on 4 July 1776, no one had been born a citizen. The declaration was a revolutionary document: it aimed to overthrow tyranny and create a new government through the power of collective action. For all its flaws, it can still today be an inspiration.