WASHINGTON — The skull of the suspected Civil War soldier arrived at the Smithsonian in a square box. The lower jaw was missing, as were four front teeth, but it was still in remarkable condition, considering it was thought to have been in the ground at Gettysburg since 1863.

The skull made headlines last year when it was saved from the auction block by public outrage. It was due for a soldier’s burial once it had been checked by the Smithsonian’s experts.

But when anthropologist Douglas Owsley set eyes on it, he knew it wasn’t as advertised.

It wasn’t from Gettysburg. And it didn’t date from 1863, the year of the battle. It was far older.

The “Gettysburg skull” was that of a young Native American man who lived about 700 years ago, 2,000 miles away in Arizona or New Mexico.

How could the skull of a man who had lived in the Southwest around the year 1300 be pegged as that of a Civil War veteran and almost get offered at an auction in Hagerstown, Maryland, last spring?

Officials at the Smithsonian, the National Park Service and the Gettysburg Foundation have reached a dead end.

“The case is suspended, pending further information,” but it’s not closed, said Ed Clark, superintendent at Gettysburg National Military Park.