For decades, the beer stein was just an old souvenir, something Ron Lenox’s father picked up in Bavaria before returning home from World War II.

Clearly, it had some historical significance. Beneath three painted crests, it bore the name von Thuengen and a military unit.

Dan Lenox and his son grew curious about the stein’s origins, but research was tough in the pre-Internet days, and their search fizzled. After his father died two years ago, Ron Lenox resumed his detective work.

This time, he solved the mystery.

Lenox, a military history buff in State College, discovered the stein belonged to Karl Freiherr von Thuengen, a decorated German army general executed for taking part in the 1944 attempted assassination of Adolf Hitler. But Lenox, 63, didn’t stop there. He tracked down a descendant, one of the last von Thuengens, and recently sent the stein back to Germany.

“It belongs with the family,” Lenox said. “There’s almost nothing left of this gentleman, as it turns out. It may be the only thing the family has of him.”

The story starts in 1946. Germany lay vanquished and in ruins. Dan Lenox, having served as a 9th Division field medic, was a hospital technician based near Ingolstadt.

One day, a man approached him on a street and offered the pewter-topped stein for a pittance. As part of the pitch, he said a high-ranking German officer had owned it. Deal.

“He liked it, and it was pretty,” Ron Lenox said.

Back in Lancaster, the stein collected dust, sometimes stashed in a closet, while Dan Lenox worked as a foreman at Armstrong World Industries.

“It never really had any importance to him,” Ron Lenox said.

His father died at 90 in 2009. A year later, the retired Armstrong research scientist moved to State College, bringing the stein with him.

He still wondered about the name and the identified unit, 17 (Bayer) Reiter Regiment. Some online sleuthing this summer revealed the answers.

Lenox, who can read German a bit, learned the 17th (Bavarian) Cavalry Regiment had been a distinguished royal outfit during World War I, its lineage stretching back to the early 1800s.

Reading further, he discovered one of the regiment’s officers in the 1920s was a former Prussian army cadet — none other than Karl Freiherr von Thuengen.

That suggested the stein had been a gift from enl isted men. Lenox kept digg ing, though, and the stein acquired more cachet.

By 1941, von Thuengen had climbed the ranks to lead the 1st Cavalry Brigade in the invasion of the Soviet Union. He next commanded tanks in the 18th Panzer Division on the Eastern Front, rising to lieutenant general and receiving the Knight’s Cross and Iron Cross medals.

Transferred to Berlin, von Thuengen was a Selective Service inspector when he joined other army generals convinced Hitler was leading Germany to oblivion. In the summer of 1944, they arrested the city’s military district commander and replaced him with von Thuengen.

After Hitler survived a mistimed bomb explosion, von Thuengen dodged the Gestapo’s wrath for a while. But he was caught, tried and, on Oct. 24, 1944, shot by a firing squad.

Given von Thuengen’s place in history, Lenox easily could have sold the stein to a World War II collector for a pretty penny. Instead, he plunged back into his research.

“As soon as I found out this gentleman was put to death for the plot against Hitler, I thought it needs to go back to the family,” Lenox said.

He found a descendant: Eric Freiherr von Thuengen, living in Thuengen, Germany. His grandfather and the general were cousins. Now, von Thuengen and his young son, Karl Kilian, are the last males in the Thuengen-Rossbach family line.

Lenox’s offer out of the blue left von Thuengen speechless. After World War II, the family castle was occupied and looted. The stein, von Thuengen thinks, may have been taken.

“It was a very wild time and people sold and stole everything just to survive,” he said in an email. “Here in town the people went to go to the castle and steal everything that the American (A)rmy did not protect or secure.”

His grandmother, he recalled, traded two bottles of schnapps for a horse and carriage to visit his grandfather in a prisoner-of-war camp.

“The stein means very much to me because it is a part of history and family returning home,” von Thuengen wrote.

He plans to place the stein with other artifacts from his family’s military service in a “special room” in his home.

Because of high airfares, Lenox declined an invitation to deliver the stein in person. But he and von Thuengen, now friends, have corresponded and talked. He can’t believe the stein made it back to Germany after 65 years.

“I’m telling you, it was so amazing to open my email that day and find an email from Eric,” Lenox said. “It was like finding a needle in a haystack.”

Chris Rosenblum can be reached at 231-4620.