This discovery marks the first time in history that a surgeon's pit at a Civil War battlefield has been excavated and studied, and is the first time that killed-in-action Civil War soldiers have been found in an amputated limb burial pit.

WASHINGTON — It’s a discovery for the history books.

The National Park Service has found the remains of two Civil War soldiers and a battlefield surgeon’s pit at Manassas National Battlefield Park.

This discovery marks the first time in history that a surgeon’s pit at a Civil War battlefield has been excavated and studied as well as the first time that killed-in-action Civil War soldiers have been found in an amputated limb burial pit, according to a park service statement.

The park service and the Smithsonian Institution recovered two complete sets of remains, 11 partial limbs and several artifacts from the site.

The two soldiers will be interred at Arlington National Cemetery later this year in coffins constructed from a downed tree from the battlefield.

These will be the first burials in the Millennium Expansion of the cemetery, according to the statement.

“This unprecedented discovery and research sheds light on military medicine during the Civil War and personalizes the human price of war,” said Manassas National Battlefield Park Superintendent Brandon Bies. “The National Park Service is honored to protect these hallowed grounds and share the stories of those who fought here.”

After the initial discovery in 2014, park service experts worked with Douglas Owsley and Kari Bruwelheide, world-renowned forensic anthropologists at the Smithsonian’s National Museum of Natural History, to excavate the site and recover the bodies and limbs.

“We’re humbled by the opportunity to give voice to their story, and we are in awe of the bravery and tenacity these men showed in the face of war,” Owsley said.

The shallow, hastily dug pit and the recovery of 11 amputated limbs confirm that this was the site of a field hospital, and further evidence tells researchers that the field hospital was used during and in the days following the Second Battle of Manassas, also known as the Second Battle of Bull Run, according to the release.

The complete sets of remains are from two white men 25–34 years old who died of injuries received at the Second Battle of Manassas.

One of the soldiers was found with an Enfield bullet still lodged in his upper thigh bone. The other soldier was found with three fired lead buckshot.

It is likely that a field surgeon determined that both soldiers had injuries too severe to be operated on successfully.

“These soldiers and the amputated limbs deepen our understanding of the techniques field surgeons used to save the wounded in the midst of battle,” Bies said. “The discovery also tells us about the difficult decisions doctors faced about who could be helped and who could not.”

Several clues tell researchers that these soldiers were from the Union Army, according to the release. Enfield bullets were used almost exclusively by the Confederate Army at the Battle of Second Manassas, and buttons from a Union jacket were found with the man who died from buckshot wounds.