William "Vern" Williams' niece and nephews and Uwe Carstens kneel beside his grave in Winfred, S.D. From left to right: Gary Williams, Kay Julius, Uwe Carstens and Ken Williams

When Uwe Carstens knelt in front of William "Vern" Williams' grave in Winfred, S.D., it was a trip that took him decades into the past, halfway around the world and brought him full circle.

Vern was killed in action during World War II, and Carstens, then age 8, had witnessed his plane crashing toward his family farm.

His nephew, Vietnam veteran Gary Williams, said Vern was a "daredevil guy," according to family lore. Vern had hitchhiked and ridden the rails out to California before his time in the military. While Gary never knew his uncle, he heard others describe him as a "fun, rather carefree" person, and as someone to be honored.

"There was always a kind of awe about that, that he was a hero. On Memorial Day from my earliest memories, we would go to the Winfred Cemetery where he was buried, and part of the program would be that the Legion would do their honor squad and shoot over my uncle’s grave," Gary said.

All the Williams family knew was that Vern had died in a B-17 in Germany. But Carstens held the keys to unlocking Williams’ family history.

Carstens remembers gathering potatoes from his family's farm on Oct. 9, 1943 outside Flensburg, Germany. It was unseasonably warm with clear skies, he said.

"At 10 a.m. we heard the thrumming of aircraft engines, and we concluded that must be Allied bombers on their way toward perhaps Kiel, our capital. Our small village was in no danger," Carstens wrote in an e-mail. "During lunch my family and I heard the rattle of machine guns and cannons fire."

His father ran outside to see what it could be, and his family followed close behind. An American bomber was ablaze in the sky, and was approaching the Carstens' farmhouse. The B-17, part of the 322nd Squadron of the 91st Bomb Group, had been attacked, and according to fellow crewmembers, Vern was killed by enemy fire. The plane was eventually shot down, but dodged the farmhouse, and crashed in an open field more than a football field away. Parachutes dotted the sky.

Carstens' father and neighbors captured the crewmembers, four of whom were brought to the family's barn. In the crowd of onlookers, Carstens stood in front.

When the German troops arrived at the scene, they discovered a dead American sergeant about 20 meters from the wreckage, Carstens said.

"He was taken into our barn. Later a coffin was brought and he was placed in it. This killed American soldier was the first dead human I had seen in my life. In the afternoon, German soldiers came and picked up the casket," Carstens said in an e-mail. The troops returned a few days later to begin collecting the debris, including three intact bombs. Two were disarmed, one was detonated.

"After holiday, when the school started again I could give my teacher and school friends a big report about a bomber crash. I think I was a hero in this moment," Carstens said in an e-mail.

The dead sergeant was buried with military honors in a nearby public cemetery. He was later re-interred in Belgium, and finally laid to rest near his home in Winfred. The story faded from the town's memory, but not Carstens'. It haunted him.

"I dreamed often about burning aircraft," he said in an e-mail. "Sometimes every night – nightmares!"

Taking the advice of a psychologist, Carstens began researching the crash in 1978. If he could find out who the soldiers were, maybe he would find closure. In the beginning, what remained unknown was overwhelming — Carstens said he couldn't even recall the date in October. He contacted the German weather service and found out Oct. 9, 1943 had been the only warm day that month.

From there, he tried the German military archives but had no luck. He eventually came across information about the U.S. National Archives in a book. The American archives gave him a full report of the event, and with that, he had names. He contacted a historical society that put him in touch with the veterans.

But after talking with them, he realized they couldn't have been the ones that landed in his field that day.

Back at square one, Carstens hunted through grave ledgers and cemeteries searching for the name of one American soldier, eventually finding "William Williams'" tombstone.

But he soon learned that hundreds of William Williamses died during WWII. He needed a middle initial.

Carstens found it after more hours of investigation, examining microfiche. He was able to make out a "V" in missing air crew reports he obtained. From there, he was able to make contact with other crewmembers and reach out to Vern's sister, who was still living, in 1983 - nearly 40 years after Vern's death.

From Carstens, they learned Vern was a waist-gunner, not a tail-gunner as they previously thought, and they had the added perspective of the final moments of his life.

When Gary and his wife decided to go to Germany in 2013, he used the address on his aunt's letter from Carstens to see if the man might be willing to meet and show them the place where Vern died.

"We wrote a letter to [Carstens] at that address in Germany not knowing whether he was dead, alive, in a nursing home or could read English or what," Gary said. In about a week, they received a reply insisting they visit.

"So we spent three days with him and just had a wonderful time. He showed us so many things and told us stories about how this all happened so we could get a better understanding of the last days of Vern's life and what happened to him," Gary said. "The place where the plane crashed is a field yet today. It's a short way from the barn, maybe 150 yards. ... Today there's no livestock there. Otherwise, pretty well unchanged from what it was at that time."

Carsten took him to the barn where Vern's crewmembers had been rounded up and where Vern was carried.

"I asked Uwe, 'Where were you standing?' and he was able to point to the spot he was standing as an 8-year-old boy," Gary said.

In May 2014, Carstens was able to visit the Williams family in Winfred. With Gary and his brother Ken Williams, they toured the house Vern grew up in. They visited Vern's final resting place.

"We went to the cemetery of course and he was able to stand on the gravesite of my uncle, and so the 71 years after he witnessed my uncle's body lying on his family farm, he was able to stand upon the ground where he was buried in Winfred, South Dakota," Gary said.

"I was very moved and crying," Carstens said about seeing Vern's grave.

"We know the whole story now of what happened to Vernon. We know how he got killed; we know when he got killed. So it just makes the whole story complete," Gary said. "And for Uwe also to come here and stand upon his grave--it was a completion of his story also."

The lifelong journey has brought closure, and new-found friendship, to Carstens.

"My nightmares have stopped," Carstens said in an e-mail.