An Australian soldier saved this drawing of Phan Thi Vu from a burning house in Vietnam in 1967 and returned it to the family after more than 40 years with the help of Operation Wandering Souls. (Courtesy of Operation Wandering Souls)

In March 1969, Laurens Wildeboer was walking outside the American base in Long Binh in South Vietnam. Just 21 years old, Wildeboer had already seen enough violence and cruelty to last a lifetime. The 14 months he'd spent in the army, he told me in a recent email, led him to "recognize the futility and criminality" of the efforts to support the South Vietnamese government.

Wildeboer is from Queensland, Australia; he was one of the approximately 60,000 Australians who served in Vietnam. (Australia and New Zealand were the only western countries to join the United States in sending troops to the war.) Wildeboer was supporting a squadron of tanks sent from an Australian base to an American one when he stumbled upon some notebooks that infantry had captured from the Viet Cong, the group in South Vietnam opposing the U.S.-backed government.

Like their American counterparts, Australian troops were told to extract from captured or killed enemy forces all notes, maps, books — anything that could potentially offer information about weapons, strategy or battlefield plans. “One booklet had the name of the author and had beautifully illustrated handwritten poetry which, at the time, immediately connected with me,” he recalls. Moved by the beauty he found amid the death and destruction of the war, he kept the documents.

Decades later, he came across an article about a project started by Robert Hall and Derrill de Heer, both Australian veterans of the Vietnam War, now at the University of New South Walesin Canberra. In 2012, as a gesture of appreciation to Vietnam for helping return the remains of six Australians who had been missing in action, Hall and de Heer put out a call to veterans’ groups and local media for items taken by Australians from the battlefields in Vietnam. They felt the objects, whatever and wherever they were, belonged to the relatives of those who had died fighting for their country. The items might also contain information revealing where the soldiers had died; Vietnam still has an estimated 300,000 missing in action from the war.

Hall and de Heer called their project Operation Wandering Souls. In traditional Vietnamese culture, if a person dies away from home, they are thought to have restless spirits. If someone dies on a battlefield and is improperly buried, his soul is considered to be wandering the country as a ghost. “These ghosts can interfere in the world of the living,” says Barley Norton, an expert on Vietnamese culture at Goldsmiths, University of London. The spirits, some believe, can take possession of living people or demand offerings in the way of food or clothing.

Through the media, Hall and de Heer made repeated appeals. They promised no questions would be asked about how people took possession of the items or what had been done with them in the ensuing decades. Over two years, Hall and de Heer heard from soldiers from Australia and New Zealand and received nearly 200 objects, including 100 letters, notebooks, drawings, photographs and even a watch. Most were accompanied by significant information about how and why they were taken.

Then came the task of finding their former owners. Nongovernmental organizations and local foreign-affairs departments in Vietnam helped de Heer and Hall track down individuals who in some cases were not aware the items existed. “It takes a lot of detective work,” notes Hall. But the two veterans found that recipients were often overwhelmed when presented with the belongings of deceased family members. “There is no hostility from the Vietnamese,” Hall says.

They found the owner of one item after a Vietnamese newspaper wrote about it. Capt. G.W. Dennis of Saddleworth, in South Australia, had sent in a framed pen-and-ink drawing of a woman. Dennis had been an Australian adviser to the South Vietnamese army. In 1967, he was moving through an abandoned village in central Vietnam when he came across a burning home, went inside, saw the picture and saved it, assuming it was a family heirloom. He held on to it for 45 years, not knowing how to return it. “He had always hoped to send it back,” says de Heer.

After the Vietnamese newspaper story about the artwork ran, a man named Le Hang recognized it immediately as his mother, Phan Thi Vu. Months later, Hang was overjoyed at being reunited with the drawing that he thought had been lost forever. The back side contained names of all Vu’s children, including his.

Hall and de Heer have reunited about 50 objects with their original owners. The rest are with the Vietnamese army. When the army or a local NGO locates the owner of one of the items, Operation Wandering Souls tries to bring Australian soldiers to Vietnam so they can hand over the items they retrieved directly to the families.

Vietnamese authorities have been accepting similar items collected by American organizations that work with veterans for years, says Joe Davis, a Veterans of Foreign Wars spokesman. VFW turns over what it receives to the Vietnamese Embassy in Washington. Vietnam Veterans of America also has an initiative to provide information about battles to Vietnamese veterans’ organizations, in order to them help locate their MIAs and burial sites. But the contact between individual Australian soldiers who discovered their items and the Vietnamese families who are receiving them marks Operation Wandering Souls as unique.

Some Australian veterans are not pleased about the project. One wrote to de Heer arguing that the focus on the well-being of the Vietnamese was misplaced. “He said: Why are you doing this?” recalls de Heer. “Why not help [us]?”

But other veterans such as Wildeboer have found the project deeply healing. “I had always had the feeling that my connection with Vietnam wasn’t complete, probably because of the documents that I still had and because I felt that what had happened to the Vietnamese was criminal,” he told me.

Wildeboer suffered post-traumatic stress disorder from his war experiences for decades. He describes himself as having had an “anti-social attitude” filled with anger, paranoia and a need for perfection, in addition to having unexplained pains in his arms and legs. “I wanted somehow to make amends, apologize,” he says.

He emailed Hall and de Heer, who sent someone to pick up the notebooks along with an interpreter to help decipher their contents. De Heer’s contacts in Vietnam confirmed the identity of the author of one of the notebooks Wildeboer had found. The creator’s name was Phan Van Ban, and his family lived outside Ho Chi Minh City (formerly Saigon). Until then, Wildeboer had never gone back to Vietnam; he had felt he couldn’t go as a tourist because of his involvement in the war. But the chance to meet personally with Ban’s family changed his mind.

Wildeboer returned in 2012 to meet Nguyen Thi Hieu, Ban’s mother, who told him that Ban died in 1970, a year after Wildeboer found his work. Hieu told Wildeboer that he gave them the only remaining records of Ban — they had destroyed all his other records in case South Vietnam government officials discovered he had joined the Viet Cong and raided the house. She was extremely grateful.

Wildeboer said the feeling of providing some comfort to her was “amazing, emotional, incredible, unbelievable.” “I had finally crossed that bridge back,” he says, “and been given the opportunity to make amends.”

Jordan Michael Smith is the author of the Kindle Single “Humanity: How Jimmy Carter Lost an Election and Transformed the Post-Presidency.”