Auction marking the United States' 250th birthday features some of its most iconic documents

As the United States prepares to celebrate its 250th birthday, an auction in New York will feature rare items that trace the nation's history.

The event Friday at Christie's, dubbed ''We the People: America at 250,'' will bring together foundational political texts, iconic American art and rare historical artifacts.

Among the highlights is a rare 1776 broadside printing of the Declaration of Independence produced in New Hampshire by printer Robert Luist Fowle, estimated at $3 million to $5 million.

''It's historically significant because you get to see what people at the time actually saw,'' said Peter Klarnet, senior specialist for books, manuscripts and Americana at Christie's.

While the initial printing was produced by John Dunlap on the night of July 4, 1776 — with about 200 copies printed and only 26 known to survive — other printers quickly began producing their own versions.

''This is the way that everyday Americans would have encountered the Declaration of Independence whether it was tacked to a wall or read from the pulpit of their local congregation,'' Klarnet said.

Another founding document up for sale is Rufus King's edited draft of the U.S. Constitution, estimated at $3 million to $5 million. Printed just five days before the final version was issued on Sept. 17, 1787, the document captures the nation's founding charter as it was being finalized.

King was a delegate from Massachusetts to the 1787 Constitutional Convention in Philadelphia. He was also a member of The Committee of Style, a five-member group tasked with refining the text.

''This puts you directly in Independence Hall as they're drafting and making the final changes and edits to this remarkable document,'' Klarnet said.

The auction also includes a signed copy of the Emancipation Proclamation. The authorized printed edition was commissioned for the Great Central Fair, a Civil War-era fundraiser held in Philadelphia in June 1864 to raise money for Union troops. The Proclamation is estimated at $3 million to $5 million.

''Lincoln, together with his Secretary of State William Seward and his Secretary John Nicolay, signed 48 copies of this,'' Klarnet said, noting they were originally sold for $20 each — and not all sold at the time.

American art plays a major role in the sale as well. Leading the category is Gilbert Stuart's portrait of George Washington — thought to have inspired the face on the U.S. dollar bill. The painting was commissioned by James Madison. It is estimated to bring between $500,000 and $1 million.

There is also Grant Wood's original pencil sketch of American Gothic drawn on the back an envelope estimated at $70,000 to $100,000.

Beyond the founding documents, the sale features rare historical objects like the only known flag recovered by U.S. forces from the 1876 Battle of Little Bighorn. The flag is expected to sell for between $2 million and $4 million.

Historians say auctions like these underscore the role of private collectors in preserving the nation's material past.

''Private collectors play an important role,'' historian Harold Holzer said. ''They save things, they preserve things, and ultimately they pass on their collections.''

For Holzer, the emotional power of the items remains meaningful.