Rear Adm. Samuel Eliot Morison was a friend to President Roosevelt who knew the ins and outs of the Navy’s strategy during World War II. He would go on to write the definitive history of the Navy’s wartime operations in a collection that spanned 15 volumes.

In February 2013, an employee at the Naval archives in the Washington Navy Yard discovered that some of Morison’s papers — a trove of maps, charts and photographs that informed his writings — had gone missing.

On Tuesday, Morison’s 69-year-old grandson was arrested and charged in the theft after some of the records turned up for sale on eBay. Samuel L. Morison of Crofton, who had already been pardoned by President Clinton for leaking classified photos to the media nearly three decades ago, is accused in court papers of stealing scores of items from his grandfather’s collection.

Federal investigators say that Morison took the documents while working as a part-time researcher at the nonprofit Naval Historical Foundation.

He tried to sell the items through a bookstore for about $20,000, according to court papers.

Paul Taylor, a spokesman for the Navy command that includes the archives, said he and his colleagues were saddened by the theft.

“We are very interested in recovering the items,” he said. “They are an important part of our history and we take very seriously our obligation to collect, preserve and safeguard our history.”

The elder Morison, who died in 1976, was a well-regarded historian who had a warship named after him. His biographies of Christopher Columbus and John Paul Jones were awarded the Pulitzer Prize.

The younger Morison revered his grandfather, a relative said, and followed his path, serving as a Navy officer during Vietnam. He later worked in the Naval History Division from 1968 to 1972, according to a biography of the rear admiral, and was a naval intelligence officer.

“This has been a difficult day,” said Morison’s attorney, Jim Wyda, the head of the public defender’s office in Maryland, who after his client’s initial appearance in U.S. District Court in Baltimore described him as frail and in poor health. “We look forward to addressing these allegations in court.”

The federal charge against Morison was not his first. Before Tuesday, Samuel Loring Morison was best known as one of the few government employees convicted under the Espionage Act for leaking classified documents to the media.

In 1985, Morison was found guilty of giving three classified spy satellite photographs to the British magazine Jane’s Defence Weekly. He was pardoned by Clinton in 2001.

Nine years later, Morison was hired as a part-time researcher in a position that gave him access to his grandfather’s historical records at the Navy archives known as “Office Files of Rear Admiral Morison Papers.”

Morison, whom relatives call “Lorry,” was extremely close to his grandfather, according to a first cousin.

His alleged conduct appears to be part of a pattern, said the cousin, Cameron Beck, who is also a grandson of Samuel Eliot Morison.

“I just think he’s always had a slight bent toward doing things that are not quite on the level,” Beck said, referring to the 1985 conviction. “He’s one of those people that never seems to have enough money.”

At a Maryland bookstore in April, Morison offered some of the illustrations, photographs and other materials his grandfather used for his Naval history books, published between 1947 and 1962.

The records, appraised at $5,000, were put up for sale at a bookstore and through eBay, according to charging papers that were unsealed Tuesday.

In May, investigators with the Archival Recovery Team within the National Archives Inspector General’s Office and a retired Navy curator visited the bookstore and identified the records as part of the government’s collection.

“Morison was never given authority to remove the records,” according to the court filing.

In a subsequent phone call with the bookseller that was recorded, Morison offered to sell another set of Navy records, stored in his home, for $15,000, investigators said.

On May 21, federal agents searched Morison’s home. They said they recovered 34 boxes of stolen records.

“Morison admitted to his theft of historical records from the Navy Archives and provided a signed statement admitting his theft,” according to an affidavit signed by special agent Brian Kelley of the Naval Criminal Investigative Service.

The theft charge against Morrison carries a prison sentence of up to 10 years, but he is likely to face far less time under federal guidelines.

“The complaint is the very beginning of a long process,” said Wyda, Morison’s attorney.

Court papers do not explain how Morison would have been able to remove so many records.

An inspector general’s report from 2011 found that the archival records were potentially at risk in part because of security. Taylor, the spokesman for the Naval History and Heritage Command, said the department has since upgraded its security systems and assigned additional curators to impose tighter control over the collection.

Maryland U.S. Attorney Rod J. Rosenstein, who has prosecuted high-profile thefts from the National Archives, said Tuesday that his office takes seriously any “evidence that historical documents are up for sale that should not be in private hands.”

Jennifer Jenkins contributed to this report.

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