A copy of the U.S. Declaration of Independence found in a records office in Chichester, England. (West Sussex Record Office Add Mss 8981/AP).

With a population of about 800,000 people, England’s quiet West Sussex region has long drawn much of its local pride from history. Its fairy-tale castles attract busloads of tourists from the capital to the countryside. During World War II, Sussex was one of the core bases to prepare the landing of the Allied forces in northern France.

Now, West Sussex has added another historical trophy: the only roughly contemporary and comparable copy of the U.S. Declaration of Independence besides the world-famous parchment preserved in the National Archives in Washington.

Harvard researchers came across the document in 2015 and announced the Sussex Declaration’s discovery last year, but it took until now to confirm the document’s authenticity.

“Our Records Office holds many fascinating treasures — but this treasure of a document is very, very special indeed,” said Louise Goldsmith, leader of West Sussex County Council.

“It is hard to explain the huge sense of history when I was so privileged to view the document,” Goldsmith said.

According to the Harvard University research, the West Sussex copy that was found in the town of Chichester dates to the 1780s, making it the only known ceremonial parchment manuscript copy of the original handwritten document that was produced in Philadelphia in 1776 and signed by the delegates to the Continental Congress.

A castle in southern England. (Niklas Halle'n/AFP/Getty Images)

Working in haste or without much experience, the creator of the Sussex Declaration rushed to finish the sheepskin document before hanging it up with iron nails, according to a detailed scientific analysis by Harvard University, the West Sussex Record Office, the British Library, the Library of Congress and the University of York.

“Tests showed congruency in the iron gall ink used throughout the document, indicating that the initial and corrected titling, the body of the text, the list of signatories, and the corrections in the text were written in a relatively short window of time, almost immediately,” according to the university's official news site, citing a still-unpublished journal piece on the research.

Hundreds of similar copies were created in the ensuing decades, and some are still preserved today.

It is still unclear how exactly the document ended up in Britain, but authorities said Monday at some point it was owned by the Third Duke of Richmond, who had supported the Americans during their fight for independence.

A politician and military officer, “radical duke” Charles Lennox championed a number of progressive policy stances, including his support for the U.S. independence movement and the need for parliamentary reforms in Britain — even though he later turned to more-conservative policies. Even though the duke had multiple children with his housekeeper, none of them inherited his properties because the relationship was declared illegitimate at the time. Much of what the duke owned was lost in subsequent years, including the declaration that would make headlines more than two centuries after his death.

In recent months, a team of Harvard researchers had carried out scientific analyses, including X-rays and DNA tests, to confirm the document’s significance.

The breakthrough came when they discovered a date hidden under an erased part of the parchment on the right side of the document's title that may read either “July 4, 178” or “July 4, 179.” Whether a fourth digit was included in the original document is unknown, but the years-long analysis concludes that the parchment was most likely produced in the 1780s.

Besides being extremely rare, the discovery may also hide a secret of historical relevance. While other 18th-century copies of the declaration listed all signatories by state, the Sussex Declaration doesn’t make that distinction.

In a forthcoming paper, the researchers argue that the declaration’s distinct treatment of signatories may indicate it was commissioned by a politician opposed to giving federal states extensive powers. Signatory James Wilson or one of his allies, the Harvard paper argues, may have been the possible commissioner of the document.

If true, the Sussex Declaration — forgotten for centuries in a dusty English archive — may be among the earliest evidence of a historic power struggle between the U.S. federal government and the states that lasts until today.

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