A previously unknown and unpublished letter from President Abraham Lincoln has been recovered for the first time.

The Civil War-era letter, which was part of a private collection for over a century, was recently identified as a document that does not appear in the definitive Lincoln collection.

The Philadelphia-based Raab Collection, the historical collector and auction house that acquired the presidential letter earlier this year, shared the details in a press release.

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The Raab Collection now intends to sell the letter at its value of $85,000.

The early Civil War letter, which is dated Aug. 19, 1861, is addressed to American civil engineer and Union Army Colonel Charles Ellet Jr.

letter penned by lincoln

The Raab Collection acquired the letter, pictured here, in early 2023 after it belonged to a private collection for over a century. (The Raab Collection)

In the note, Lincoln documents his wartime strategy, highlighting political tensions and revealing the science behind protecting Washington, D.C., according to Nathan Raab, principal of The Raab Collection.

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The letter reads, "You propose raising for the service of the U.S., a Civil Engineer Corps. I am not capable to judge of the value of such a corps, but I would be glad to accept one if approved by Gen. Scott, Gen. McClellan & Gen. Totten. Please see them and get their views upon it."

In the note, Lincoln documents his wartime strategy, highlighting political tensions and revealing the science behind protecting Washington, D.C. (Library of Congress Prints and Photographs)

"Discovering unpublished, unknown letters of Abraham Lincoln is increasingly rare," Raab wrote in the press release.

With this new addition to history, the Raab Collection said this letter "fills in a part of the historical record that had been missing" regarding the need for a corps of civil engineers to "survey terrain, disrupt Confederate supply chains and defend the city of Washington."

lincoln next to his letter

"Discovering unpublished, unknown letters of Abraham Lincoln is increasingly rare," Raab wrote in the press release. (Library of Congress/The Raab Collection)

Ellet, who died in 1862, was considered the greatest civil engineer in the U.S. during this era, according to the Raab Collection.

Ellet had previously pushed the president to better support the Army’s Corps of Engineers, and the Civil War further highlighted the need for funding and equipment, as Washington, D.C., was potentially in danger.

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In the letter, Lincoln instructed Ellet to discuss the matter with Gens. Scott, McClellan and Totten.

charles ellet political cartoon

The early Civil War letter, dated Aug. 19, 1861, is addressed to American civil engineer and Union Army Colonel Charles Ellet Jr., depicted here in a political cartoon. (Library of Congress Prints and Photographs)

When the letter was delivered to McClellan's home, the general snubbed the president by refusing to speak with Ellet, according to Raab —  who cites the letter as documented evidence of McClellan’s mistreatment of Lincoln.

When a fleet of Union boats was destroyed in 1862 by the Confederacy’s USS Merrimack, the generals realized that Ellet was right.

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"Abraham Lincoln autographs and historical documents are among the most collected and are always in demand," Raab Collection notes on its website. 

"His letters are known for their great clarity and economy of words — he never [used] two where one would suffice."

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The Lincoln letter is currently for sale at raabcollection.com.