William 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, Va. He was 84.

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

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.

As the chief historian and principal author of the reports, 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.