About 150 members of the nation’s largest nonprofit organization devoted to Civil War battlefield preservation are in Vicksburg this weekend.

Representatives of the Civil War Preservation Trust, which conducts annually what members call a grand review, are in Vicksburg for the first time.

Melissa Meisner, director of events for the CWPT, said the visit to Vicksburg, like all others, is to allow the trust’s color bearers, or individuals who donate at least $1,000 a year to the organization, to tour Civil War battlefields.

“The grand reviews are a nice way of letting our color bearers see what good their donations are doing,” said Meisner, also the CWPT’s color bearer coordinator.

The group kicked off the weekend Friday evening with tours of Vicksburg’s historic homes. Today, they will head to Hinds County to visit Dillon Plantation and Champion Hill.

A dinner featuring Jeff Shaara, author of the Pulitzer prize-winning novel “Gods and Generals,” is set for tonight, and on Sunday the group will tour the Vicksburg National Military Park.

This year’s tour group includes about 10 employees from CWPT’s headquarters in Hagerstown, Md., and about 140 color bearers from across the country.

For John Bamberl, a color bearer from Scottsdale, Ariz., this was his first trip to Vicksburg. However, he has read books on the Vicksburg Campaign of 1863.

“This was a very pivotal and decisive battle — very crucial to the outcome of the Civil War,” Bamberl said.

Also on the group’s agenda this weekend is presenting VNMP Park Historian Terry Winschel with the 2007 CWPT National Park Service Preservationist of the Year award, an honor announced in April. Winschel will serve as a tour guide for the group.

“We would like to someday preserve the entirety of the Vicksburg Campaign, which encompasses hundreds of square miles,” he said. “This trust is crucial in accomplishing something like that.”

The CWPT, formed in 1999, uses the donations of its nearly 70,000 members, about 500 of which are color bearers, to purchase places significant to Civil War history and convert them to historic sites and parks, said Mary Goundrey, the organization’s deputy director of communications.

The organization was created from two trusts — the Association for the Preservation of Civil War Sites and the Civil War Trust. The CWPT has preserved more than 24,000 acres in 18 states, including 4,206 acres in Mississippi and 1,573 acres related to the Vicksburg Campaign. Last year, the CWPT’s color bearers toured Charleston, S.C. Next year, they will travel to Washington, D.C.