William Z. Slany, a top State Department historian who helped oversee a study in the 1990s that exposed Nazi looting of Jewish property and that led to $8 billion in belated compensation for Holocaust victims and their families, died May 13 at his home in Reston. He was 84.

The cause was heart ailments, said his former wife, Beverly Zweiben.

Dr. Slany was the State Department’s chief historian from 1982 until his retirement in 2000. He drew the most attention for a massive, two-part study that burrowed into the history of Nazi Germany to expose the methodical theft of Jewish property.

The stolen assets encompassed jewelry and other valuables belonging to victims of the regime’s persecution. The looting was so extreme as to include gold teeth taken from concentration camp victims.

In addition, many European Jews had turned to Swiss banks for safekeeping of their savings during Hitler’s rule. Many of those account holders did not survive the Holocaust. Decades later, questions remained about the status of their assets.

William Z. Slany helped oversee a study in the 1990s that exposed Nazi looting of Jewish property and led to $8 billion in belated compensation for Holocaust victims and their families. (Family Photo )

A new wave of interest in the dormant, unclaimed accounts came in 1995, after then-Sen. Alfonse D’Amato (R-N.Y.) launched Senate banking committee hearings after being urged on by the World Jewish Congress.

The next year, President Bill Clinton tapped Stuart E. Eizenstat, an undersecretary of state who had served as a special envoy for property claims in Central and Eastern Europe, to investigate. Eizenstat asked Dr. Slany to help.

As the chief historian and principal author of the reports, Dr. Slany oversaw the declassification of nearly 1 million pages of documentation and the indexing of more than 15 million pages by the National Archives and Records Administration.

With contributions from 11 federal agencies, the report was one of the largest interagency historical efforts undertaken by the executive branch.

In an interview, Eizenstat praised Dr. Slany’s “credibility, integrity [and] sharp historian’s eye.”

“They should have been called the Slany Reports because he was the one that envisioned the work plan, stitched together the information, and drafted the report,” he said. “This was his product from start to finish.”

According to the investigation, many of the stolen assets were stored in ostensibly neutral nations, including Sweden, Portugal, Spain, Turkey and Argentina. The report’s sharpest criticism was of Switzerland, which was estimated to have possessed as much as $400 million in looted gold.

“The massive and systematic plundering of gold and other assets from conquered nations and Nazi victims was no rogue operation,” Eizenstat said in the 1997 preliminary report. “It was essential to the financing of the German war machine.”

That report also emphasized the shortcomings of the United States, particularly government officials’ reluctance after the war to aggressively seek compensation for Holocaust victims.

Jim Hoagland, a Washington Post foreign affairs columnist, called the preliminary report “a Matterhorn of integrity and truth-telling.” The initiative encouraged more than a dozen nations to set up their own investigative commissions. It also has been credited with setting the groundwork for later settlements, including a landmark $1.25 billion settlement by Swiss banks with Holocaust survivors and their families.

Eizenstat said the findings also prompted governments to resolve other wartime reparations issues, including the return of stolen art and unpaid insurance policies for Holocaust victims stemming from World War II.

“Never have I had such an opportunity to apply my skills and experience as a historian to so worthy but difficult a challenge,” Dr. Slany said in 1997 testimony before the Senate Committee on Banking, Housing and Urban Affairs.

William Zweiben Slany was born in Cleveland on July 23, 1928. He was an Army veteran of World War II and participated in the postwar occupation of Japan. He was a 1951 graduate of Ohio University and received a doctorate in Russian history from Cornell University in 1958.

Around that time, Dr. Slany joined the State Department’s Office of the Historian. He helped produce 222 volumes of the “Foreign Relations of the United States,” which since 1861 have served as a historical record of U.S. foreign policy decisions.

Some historians considered the books incomplete because they neglected the role of the intelligence community in shaping American foreign policy. Dr. Slany played a role in the passage of the 1991 statute that required the CIA and other intelligence agencies to cooperate on the volumes and in other research. Later in the decade, he openly scolded the spy agency for what he believed to be “unreasonable excisions” in their declassification of Cold War activities.

“What has become apparent and obvious is the agency’s unwillingness to acknowledge amounts of money, liaison relationships, and relationships with organizations, information that any ‘reasonable person’ would believe should be declassified,” Dr. Slany stated in a 1999 State Department Historical Advisory Committee meeting. “The process has revealed the bare bones of the CIA’s intransigence.”

Upon his retirement, Dr. Slany received the Secretary’s Distinguished Service Award from the State Department.

His marriages to Elizabeth Ballas and Beverly Zweiben ended in divorce. Survivors include one brother.