New York Times employees in the Saigon bureau in 1965: Nguyen Ngoc Rao, the office assistant, (standing) and, from left, Peter Grose, Seymour Topping and Jack Langguth. (The New York Times)

A.J. “Jack” Langguth, a former foreign correspondent, University of Southern California professor and war historian whose book on the Vietnam conflict was widely admired for a narrative sweep that gave serious weight to the perspectives of ordinary North Vietnamese and their leaders, died Sept. 1 at his home in Hollywood. He was 81.

The cause was respiratory failure, said Charles Fleming, a close friend and Los Angeles Times journalist.

Mr. Langguth, whose newest book is due out this month, joined the New York Times in the early 1960s and, in late 1963, he secured a rare interview with the mother of Lee Harvey Oswald soon after Oswald’s arrest in the assassination of President John F. Kennedy.

The following year the paper dispatched Mr. Langguth to Vietnam, making him its Saigon bureau chief in 1965. On subsequent trips he covered the aftermath of the Tet Offensive in 1968 and the U.S. invasion of Cambodia in 1970.

Unable to set Vietnam aside, Mr. Langguth spent seven years researching and writing the award-winning “Our Vietnam: The War 1954-1975” (2000), which won acclaim for telling the Vietnamese side of the story as well as it did the American side, through solid analysis, mastery of detail and deft portraits of pivotal figures, including Defense Secretary Robert McNamara and South Vietnamese President Ngo Dinh Diem.

“The book does not develop new arguments or explicitly address the many war issues that still divide Americans,” historian George C. Herring wrote in a 2000 review for the Los Angeles Times. “Its strengths, rather, are in its skillful retelling of a well-known story, and in the way it captures the many dimensions of the war.”

Herring noted that Mr. Langguth’s interviews with North Vietnamese and National Liberation Front leaders as well as ordinary Vietnamese were “especially valuable in filling in that essential, but for Americans, often-neglected side of the war.”

Mr. Langguth, a USC journalism professor for 27 years before his retirement in 2003, said he conceived the book in part because of his students’ ignorance of the war that ended before they were born.

“One of the reasons I wrote the book was the hope that if you just laid out the story in a nonpartisan way, they would . . . understand what was going on at a time when their fathers and uncles were pretty divided over the issue,” he told the Los Angeles Times in 2001.

Mr. Langguth wrote a dozen books, including three novels, a biography of H.H. Munro — the British playwright and short story writer better known by the pen name Saki — and books involving the American Revolution (“Patriots: The Men Who Started the American Revolution,” 1988), Caesar’s struggle for Rome (“A Noise of War,” 1994), the War of 1812 (“Union 1812,” 2006) and the period leading to the Civil War (“Driven West: Andrew Jackson and the Trail of Tears to the Civil War,” 2010).

His latest book, “After Lincoln: How the North Won the Civil War and Lost the Peace,” will be published this month by Simon & Schuster.

Arthur John Langguth was born July 11, 1933, in Minneapolis, where his father worked in the grocery business. He once described Minneapolis as a great place to raise children “if you wanted them to be insurance salesmen. I wanted to be a writer.”

He was thrilled to escape the Midwest for Harvard University, where he edited the Crimson student newspaper with his classmate and future war correspondent David Halberstam. After graduating in 1955, he served in the Army from 1956 to 1958.

He started his journalism career in 1959 as a Washington, D.C., correspondent for Cowles Publications, then covered the 1960 presidential election for Look magazine.

Mr. Langguth said his experiences covering the war probably led to his fascination with bloody turning points in American history.

Watching “the way that raggedy group of [Viet Cong] were beating the greatest army on Earth brought to mind the way the revolutionary soldiers — ill-organized, ill-equipped — brought the greatest power of its time to its knees,” he said in 2001. “And so when I did the book on the American Revolution, I was very aware of how patriotism, the desire for freedom, can motivate people to fight well past their limits.”

Mr. Langguth never married and had no immediate survivors.

— Los Angeles Times