An art restorer made the discovery, that a portrait hanging in Springfield Illinois of Mary Todd Lincoln wasn't actually her at all.
Apparently painted by Francis Carpenter, it was supposed to have been a gift, from Mary to her husband. Now this bit of history appears to be fiction.
James Cornelius, Curator of the Lincoln Collection at the Presidential Library and Museum says, "We don't know who the sitter is. We don't know who the artist was."
Experts say the truth about this painting is that it's a fraud: the work of a "con" artist looking for money.
Lincoln family members who purchased the painting back from a collector in 1929 had no idea.
Cornelius says, "Somebody tried really hard to completely obscure the origins of that painting."
But art conservator Barry Bauman wasn't fooled.
Hired to clean the work, he quickly noticed the work had been modified.
For starters, the subject's facial features had been changed and her hair.
Then there was her jewelry: a cross had been hidden, a brooch of Abraham Lincoln added.
And the artist's signature was irregular too. It had been added over the varnish.
Bauman says, "Not only is it not Mary Lincoln, it's not Francis Carpenter."
The curator at the Lincoln Presidential Library and Museum was shocked.
Cornelius says, "You don't think twice when an item comes directly from the family."
At an event to mark Lincoln's birthday, the fake painting was a hot topic, especially among historical reenactors.
Brian Miller says, "It was a surprise at the same time it is a little sad."
Laura Reyman adds, "People want to believe that they have a piece of history."
Jonathan Reyman says, "I'm a curator at the Illinois State Museum and we're talking now about doing an exhibition of forgeries. So this would fit right in with it."
But the painting will be staying put.
Bauman says, "It's right now, the museum's most famous painting."
The museum's curator says as a gift from the last of the Lincoln descendants, it still has value.
Cornelius says, "It's worth less now in financial terms, but it's still worth a lot in historical and story terms."
A lecture about the museum's findings is set for April 26th.