(CNN)On June 19, 1944, Julius and his twin brother Ludwig Pieper were on a vessel bound for Utah Beach on the Normandy coast of France -- 13 days after D-Day -- when it struck a mine and sank.
Twin brothers died the same day in France during World War II. 74 years later they were reunited at Normandy
The two Nebraska brothers, both Radiomen 2nd Class in the US Navy, were among the 117 sailors to die in the wreck.
But while Ludwig Pieper's remains were identified soon after, those of Julius Pieper weren't found. Officials declared him missing in action -- until last year, when a remarkable series of events led to Julius being identified as well.
Now, 74 years to the day after the brothers were last alive together on their doomed Landing Ship Tank (LST)-523, they have finally been reunited -- buried side by side by their family this week at Normandy American Cemetery in France.
According to the American Battle Monuments Commission, the twins' family buried Ludwig at Normandy's American Cemetery in 1944.
The name of his twin brother, Julius, was inscribed on the Walls of the Missing at the cemetery, as the whereabouts of his remains were unknown.
In 1961 a crew recovered some human remains from LST-523, but they were unable to identify them. So officials buried the remains in Ardennes American Cemetery in Belgium under an unknown headstone.
This was not unusual. For decades, thousands of unidentified American remains from World War II rested in the grounds of the American Battle Monument Commission's cemeteries.
Currently 72,917 service members are still unaccounted for from World War II, says the ABMC.
As technology advanced, the Department of Defense increased its efforts to identify the thousands of lost American service members from World War II, Korea and Vietnam.
In 2015, Pentagon officials decided to dig up the unknown remains buried within all of the ABMC World War II cemeteries.
But they didn't know they had a special ally in Ainsworth, Nebraska: Vanessa Taylor, a high school student who was assigned a World War II research project.
"It was my sophomore year, and we had to pick one hero from World War II from our state that had to be buried in that cemetery. After I read the database they gave us in class, I chose the twins," Taylor told CNN.
As she began researching the Piepers, Taylor found the brothers' surviving family through information obtained by the Defense POW/MIA Account Agency.
The DPAA became curious of her findings, and after a little more digging, they discovered a possible link between Julius Pieper and the LST-523 remains recovered in 1961.
"We traveled to France to visit the cemetery, as a part of the project. When we were there I met with someone from the DPAA who told me they had found a piece of a personal identification that matched part of his name and a wallet, so they decided to investigate further," Taylor said.
So the DPAA exhumed the remains in 2016 and conducted a series of analyses from dental, anthropological and chest radiography records. That, combined with other circumstantial and material evidence, led to the identification of Julius in 2017.
Now the family had to make a decision: Did they bring Julius' remains back to the US or bury him near his brother and the battlefields of Europe?
Knowing how strong a bond exists between twins, the family came to the conclusion that Julius and Ludwig had been separated for way too long.
Since Ludwig was already resting in Normandy, the family chose to have Julius buried next to him. Six family members traveled to France for Tuesday's interment.
Burials within ABMC cemeteries are rare today, as these cemeteries are considered closed -- except to remains recently recovered and identified, as in the case of Julius Pieper.
CNN has reached out to the Pieper family for comment.
"I'm overwhelmed with the beauty of the cemetery," Dean Lawrence, the twins' nephew, told the ABMC. "And I'm comfortable in knowing my uncles are here, where other people can learn their stories."