CHICAGO (NewsNation) — A 21-year-old sailor will be laid to rest Tuesday following a decades-long effort to identify remains pulled from Pearl Harbor, more than 80 years after he was killed in the attack that propelled the United States into World War II.

Members of Herbert “Bert” Jacobson’s family have waited all their lives to attend a memorial for the young man they knew about but never met. Jacobson was among the more than 400 sailors and Marines killed on the USS Oklahoma during the Dec. 7, 1941, Japanese attack on Pearl Harbor. The casket containing his remains will be interred at Arlington National Cemetery.

“This has kind of been an unsolved mystery and it gives us closure to finally know what happened to Bert, where he is and that he’s being finally laid to rest after being listed as an unknown for so long,” said Brad McDonald, a nephew.

The service at Arlington will be the latest chapter in the story of the man from the small northern Illinois town of Grayslake, for the family that never had a body to bury when he was killed and the scientific quest to put names to the remains of hundreds of personnel from the battleship who lay buried anonymously for decades in a dormant volcanic crater near Pearl Harbor.

The Associated Press contributed to this report.