They were part of his family, participants in history. David Holmes was familiar with each photo in the album — the men in uniform, the women uniformly peering into the distance as if their men were already gone.

For years, the Marietta resident kept the aged, leather-bound book containing the photos, bringing it out occasionally to entertain visitors or to show his daughters from where they came.

No longer. The album, said Holmes, has “gone home.” The book that had been in his family for 150 years has been given to a historical society in the town where many of those fierce-eyed men and women lived. It is to be put on display May 18 in a pre-Memorial Day ceremony that will take place in the Carrollton, Ohio. It will take place at the house the patriarch built 180 years ago, now a Civil War museum.

“History is something you want to share,” said Holmes, 60.

They were known as the “Fighting McCooks,” three brothers and their sons — 15 sons in all — who served the Union during the Civil War. Holmes’ photo album contains the images of the senior brother, Daniel, and nine of his sons, as well as daughters, wives and children. He got the book from his dad, who traced his ties to the folks in the album to a great-great-great grandmother.

On a recent morning, Holmes recited a short biography of each: Daniel and Daniel Jr., the father killed at Buffington Island, Ohio, and his son slain at the Battle of Kennesaw; Latimer, twice wounded; George, who made it through unscathed. They fought from one end of the war to the other.

He thought about selling the album, but changed his mind.

“I was afraid it would be split up,” and the photos sold individually, Holmes said. “I couldn’t stand that.”

Instead, Holmes tracked down the phone number for the Carroll County Historical Society in Carrollton, Ohio. He made a call. Society President David McMahon answered.

Holmes didn’t waste much time. Would McMahon be interested in a family photo album highlighting Carrollton’s most renowned family?

McMahon was skeptical. Who was this guy calling from Georgia?

“I hate to say it, but you have to question something when it sounds too good to be true.”

Holmes insisted that he was legitimate — as was his offer. In December, Holmes and his wife, Patti, drove 10 hours to deliver the album to the eastern Ohio city.

McMahon is still thrilled with the gift. “This is really a special deal,” he said. “This is a special addition to the collection.”

It’s hard to understate how large the McCook family looms in the history of Carroll County and the Civil War.

In 1837, the elder McCook, Daniel Sr., built a home on the square in Carrollton. When war broke out, he joined the fight. Daniel Sr. was 63. His sons followed, as did six nephews.

They fought at Vicksburg and Bull Run, at the Battle of Atlanta and Chichamauga. A monument to Dan Jr. stands at the Kennesaw Mountain Battleground National Park.

“You couldn’t hardly go anywhere without tripping over one of those McCooks from Ohio,” McMahon said.

At war’s end, many of the surviving McCooks moved on to successful civilian lives. One son became the state’s attorney general and was a candidate for governor. Another became a well-known lawyer in New York. A third was governor of the Dakota Territory, but was assassinated. The McCooks and their descendants spread across the country, with the Holmeses coming to Georgia in the early 1950s.

The house the elder McCook built still stands on the square in Carrollton and is now a Civil War museum. It will house the album.

The album shows how important photography had become by the time war broke out in 1861, said Bob Zeller, president of the Center for Civil War Photography. The nonprofit group, founded in 1999, routinely fields inquiries from people wanting to learn more about family Civil War photos.

The center isn’t likely to run out of emails or calls. Millions of soldiers and their families sat for portraits during the Civil War.

“Nearly every soldier had his portrait taken,” said Zeller.

But how many family albums are out there? Holmes believes the album is unusual, if not unique.

“We’re glad to give it to them,” he said. “This was the right thing to do.”