Allen Weinstein, a historian of Cold War espionage whose 1978 book, “Perjury: The Hiss-Chambers Case,” marshaled a mountain of new evidence to argue that Alger Hiss was guilty as charged in one of the most famous spy trials of the postwar era, and who served as the ninth national archivist of the United States, died on Thursday at a nursing home in Gaithersburg, Md. He was 77. The cause was pneumonia, his son Andrew said. He had been suffering from Parkinson’s disease for several years. Making use of newly available F.B.I. documents totaling tens of thousands of pages, Mr. Weinstein...