A descendent of Ulysses S. Grant may possess the last known photograph of Abe Lincoln before his assassination, some believe:

If it is indeed Lincoln, it would be the only known photo of the 16th president in front of the executive mansion and a rare find, as only about 130 photos of him are known to exist. A copy of the image was provided to The Associated Press.

Grant's 38-year-old great-great-grandson, Ulysses S. Grant VI, had seen the picture before, but didn't examine it closely until late January. A tall figure in the distance caught his eye, although the man's facial features are obscured.

He called Keya Morgan, a New York-based photography collector and Lincoln aficionado, who helped identify it as Lincoln.

"I was like, 'I don't know who this is, Keya,'" said Grant, a Springfield, Mo., construction business owner.

Although authenticating the 2 1/2-by-3 1/2-inch photo beyond a shadow of a doubt could be difficult, several historians who looked at it said the evidence supporting Morgan's claim is compelling and believable.

Prior to this discovery, the last known photograph of Lincoln is widely believed to be this, taken on March 8, 1865, a little more than a month before he was assassinated:

Well, let's have a look at the newly discovered photo:

Let's blow it up to see (supposedly) Abe:

There is handwriting on the back of the photo saying “Lincoln in front of the White House”, as well as the date 1865 and the seal of photographer Henry F. Warren.

I can buy that the tall man, apparently with a beard, is Lincoln.  I'm not convinced it is necessarily the last photo of him.

Warren took the photo at the top of this post, widely believed to be last photo of Lincoln.  So the newly discovered Lincoln photo bearing Warren's sesal may have been taken on the same photo session.

But Warren's notes suggest that he took three photos that day.  The first one was supposedly a "standing shot"; the latter two were head and chest.  Warren's first photo (or its negative) have never been seen. 

Which raises the question: is this [the newly discovered photo] the first of Warren's three photos?  If so, then it is not the last photo of Lincoln.

This doesn't undermine the historical importance.  Any photo of Lincoln is an historical find.  And if this "new" photo is, in fact, Lincoln, it is the first known photo of any President in front of the White House.