What strikes Howard Lambert most is how casual the reference was, written in a Confederate soldier’s diary, between bland notes on his unit’s movements and on finding abandoned enemy provisions.

“We captured three Negro soldiers, the first we had seen,” Private Byrd Willis wrote on May 8, 1864. “They were taken out on the road side and shot and their bodies left there.”

Coming across these lines a century and a half later was “a chilling experience,” Lambert said in a phone interview. “It was like a common occurrence. No ceremony, just, ‘Oh, we lined ‘em up and shot ‘em.’ “

On Saturday, the three unknown soldiers of the U.S. Colored Troops will be honored in Culpeper County, Va., not far from where they were executed. It’s part of a years-long effort by Lambert, the head of the nonprofit Freedom Foundation, to highlight the area’s Black history, working together with Civil War Trails and the Piedmont Environmental Council.

Saturday’s ceremony will unveil the Maddensville Historic Site on Madden’s Tavern Road, which includes a granite obelisk commemorating the three men and three historical markers from Civil War Trails explaining other aspects of the area’s history.

Lambert, a native of Culpeper County, has been fascinated for decades by the U.S. Colored Troops, the U.S. Army regiments in the Civil War recruited among free and newly freed Black men. He has researched their history, participating in living history events as a reenactor and even appearing as an extra in movies like “Glory” and “Lincoln.” A semiretired defense contractor, Lambert now spends much of his time back in his home county sharing his research.

At least 160 battles during the Civil War were fought in Culpeper County, according to the local tourism bureau. And though the county, as part of Virginia, sided with the Confederacy, more than a hundred Black men born there went on to serve in the U.S. Colored Troops, Lambert said.

“These men who left, they didn’t have to come back,” he said. “They could have stayed at Freedman’s Village and enjoyed their freedom. But they felt the need to free the rest of [the enslaved].”

Black soldiers were often assigned to guard the rear as troops moved into position for battles. It is likely the three men were captured while guarding supply wagons for soldiers fighting in the Battle of the Wilderness, according to Lambert.

The Confederacy did not recognize U.S. Colored Troops as soldiers but as enslaved people in a state of insurrection, and as such it did not follow the prisoner-of-war rules it used for White Union troops. Instead, captured Black soldiers were either sold into slavery or, like the anonymous men on May 8, 1864, summarily executed.

The signs at the new historical site will also honor Willis Madden, a free Black man whose mother had once been enslaved by President James Madison, and who, in 1840, opened the only Black-owned-and-operated tavern in the antebellum Piedmont, the hilly region between the Atlantic coastal area and the Appalachian Mountains. Madden was well-respected and purchased hundreds of acres of farmland in Culpeper County, eventually donating land and materials for the construction of the Ebenezer Baptist Church, which still stands across the street.

“To me, it’s like the American story: You work hard, you start your own business, and you do well,” Lambert said. “And he’s certainly a symbol of that.”

Present-day congregants of the church, descendants of Black Civil War veterans and members of the Madden family will all attend the unveiling ceremony Saturday, Lambert said.

Lambert is working on a number of other projects in the county, including a historical marker about U.S. Colored Troops recently approved by Virginia’s Department of Historic Resources. That marker will go up next year at Brandy Station, seven miles northwest of the Maddensville site.