McCallie School Upper School Associate Headmaster Kenneth Sholl speaks about a plaque that will be installed at the school remembering lives lost on the campus grounds during the Civil War.

On the land beneath McCallie School a battle raged 150 years ago this month.

Wednesday 654 boys heard a sweeping narrative of how blue and gray collided on the "very ground" they walk each day.

Jim Ogden, chief historian at Chickamauga and Chattanooga National Military Park, opened his talk in the school's chapel with a description of the living conditions of Confederate soldiers encamped on the grounds from September through November of 1863.

They dug out shelters and made small huts to keep out the cold. It rained on 19 days of their three-month stay.

Then came the Union troops.

"On Nov. 23 [with the Orchard Knob assault] your campus became a battlefield," Ogden told the students.

Union soldiers began moving toward the rebel soldiers from near Orchard Knob, a short distance away. Confederates were stationed along where cars now drive on Dodds Avenue.

A Confederate officer spotted the blue advance and described it as follows:

"The enemy, like a huge serpent, uncoiled his shape ... " Ogden recounted.

Boys, as young as some seated in the McCallie Chapel on Wednesday, heard screeching cannonballs and watched as lead mangled bodies.

An estimated 1,000 men died. Another 7,000 were injured in the battles that crisscrossed what would become the school's campus.

"On this field of chaos, a school was born," McCallie Headmaster Kirk Walker said.

Forty-two years after the battle, in 1905, sons of the Rev. T.H. McCallie formed the school with their father's donation of the land. The pastor had preached to both Confederate and Union troops during the battles and later occupation of Chattanooga.

The school dedicated a bronze plaque with a quote from President Abraham Lincoln to commemorate the 150th anniversary of the Nov. 25, 1863, battle of Missionary Ridge.

The plaque will be placed behind the school's flagpole next to the Memorial Wall. It was donated by Keo Kio, the school's senior leadership organization.

At least three at the school today can trace blood relatives to the fighting.

Ches Graham, a 17-year-old senior, has two relatives, brothers with the last name Carey, he's told, who fought with an outfit out of Georgia.

Graham's grandfather, Roger Johnson, took him to reenactments as a boy and shared what he knew of the family history.

Seeing places on campus where his ancestors fought brought the story to life, he said.

Throughout the week students are discussing aspects of the war in nearly all of their subjects from the obvious, history, to the not-so-obvious, math.

Boys will plot the trajectories used in artillery, learning how soldiers had to use math on the fly in a time unaided by digital technology.

As in Ogden's talk, a good starting point is the battles, which usually grab a boy's attention, said Kenny Sholl, head of the Upper School at McCallie.

"We tie it as much as we can to character and leadership," Sholl said. Teachers work to show the larger context on why the war happened, its importance and what can be learned.

The educator is steeped in Civil War history himself. He has two ancestors through blood relation and one through his wife's family who fought, all at or near the local battles.

In his family, a Union soldier named Digory Sholl marched with his Ohio unit through the South and fought at Citico Creek. Another ancestor, a Confederate soldier named William H. Logan, camped where the northern end zone of the school's football field now.

Sholl learned of that historic connection about six years ago. Now a map of the unit positions during key battles hangs in the school's dining hall with an overlay of today's campus.

Bob Biers, dean of student life, came to McCallie 31 years ago from Pittsburgh, Pa.

He knew he had Civil War connections, but it wasn't until a few years ago that he learned of the direct ties to the campus.

A Union soldier named Mervin Barber fought on the land with a New York regiment.

Sholl and Biers, both 56, started working at the school the same year.

Through their research they've discovered that their relatives likely clashed in the local battles, with Sholl's Confederate ancestor defending and Biers' Union ancestor attacking.

"And I won," Biers laughed.

"He reminds me of that quite often," Sholl responded.

Contact staff writer Todd South at tsouth@timesfreepress.com or 423-757-6347. Follow him on Twitter @tsouthCTFP.