At 11 a.m. tomorrow -- the 11th hour of the 11th day of the 11th month -- we will mark the moment at which in 1918 the transaction ending the War to End War was achieved. For years, we celebrated Nov. 11 as Armistice Day. Now it's called Veterans' Day. Fine. War did not end. So it's fitting to honor those who have sacrificed in subsequent state-sanctioned bloodshed.

And tomorrow there will go on the market a book that has much to say about sacrifice and bloodshed and why wars endure. That book is To America: Personal Reflections of a Historian, by Stephen Ambrose (Simon and Schuster, 288 pages, $24).

Ambrose, a cigarette smoker, died at 66, on Oct. 13, of lung cancer. He worked almost to the day of his death, as he had all his life, taking joy in research and writing. He loved history. But he loved stories even more. It was the stories that constitute history that lured him away from his pre-med studies in college.

He wrote books at what seemed superhuman speed, and in immense numbers -- 35 volumes. He served as professor in a number of universities, including Johns Hopkins, where he taught history while working on the papers of Dwight Eisenhower. He led a vast number of history-related projects -- films, television series, exhibitions. He founded and worked mightily for years to fund the National D-Day Museum in New Orleans, which he often said was "by far the thing I'm most proud of." His popular success as a writer is attested to by the fact that he gave more than $2 million of his own royalty money to that effort.

In this, his final work, he wrote of that project and much else. The book is part sermon, part celebration, part declaration of faith by an American who -- for all this nation's unresolved failings -- doubts not for a moment that it is the greatest and most benevolent country on earth in the best of times in human history. Ambrose was immensely, unequivocally proud of the United States of America. This is a patriot's paean.

It is also a very personal memoir. There is a delightful chapter on three summers of camping with his wife and children near the site of the Battle of Wounded Knee and traveling through Montana, South Dakota, Wyoming -- making a family project of his book on Gen. George Custer and Chief Crazy Horse.

A particularly fascinating and substantial aspect of this book is Ambrose's tracing changes of fads of history among academics. Ulysses Grant was a great hero to Americans in the 19th century, who regarded his high casualties in battle as a necessary supreme sacrifice. World War I, with its massive death tolls, led revisionists to view Grant's losses as squander, and Grant as a pariah.

Confronting his early acceptance of this faddish appraisal, Ambrose writes, "I've always been ready to praise Grant as a general, damn him as a politician. I was especially furious at the way he gave in to, or sold out to, the white supremacists. Today I know that he tried to do more for the African-Americans than any President until Lyndon Baines Johnson." He makes Teddy Roosevelt out to be a truly great president despite all of the snide condescension and dismissal by the mainstream political historians of a generation and two ago.

Writing about the building of the transcontinental railway -- and the academic doctrine that its builders were despicable "robber barons" -- Ambrose insists that without them, it would have taken another generation or two to span the continent, which cut the travel time from New York to San Francisco from six months to seven days. Thus, he writes, it is more appropriate that "we admire those who did it -- even if they were far from perfect -- for what they were and what they accomplished and how much each of us owes them."

An antiwar radical, opposed to the U.S. role in both Korea and Vietnam, Ambrose was a chaired professor at Kansas State University when his disruptive protest of a speech in 1970 by Richard Nixon led to a rift that forced him off the faculty. He moved to Louisiana State University, where he stayed, but for sabbaticals and visiting professorships, the rest of his days.

But writing always took first place. His defining biography of President Eisenhower took many years. That further whetted his fascination with military history -- and battle and soldiers. Never having worn a uniform himself, he came to respect profoundly the self-sacrificing nature of soldiers.

Although Ambrose at first flatly rejected the idea, Alice Mayhew, his editor at Simon and Schuster, persuaded him to begin a biography of Richard Nixon. He spent 10 years researching and writing it -- in three volumes -- without ever being granted a single interview with the man. He never came to like Nixon, though after writing 2,155 pages about him he came to respect him -- and felt he almost understood him.

In the last year of his life, Ambrose faced -- and essentially shrugged off -- accusations that some his work contained plagiarized language. Some sentences in his 2001 The Wild Blue were identical to language in Thomas Childers' Wings of Morning. Ambrose's defense was that his book's footnotes gave credit, and the fact that the text did not cite the specifics was inconsequential. Two other of his books contained material of similarly questionable attribution.

I am not certain where the truth lies on this issue, though I lean toward crediting Ambrose's intellectual integrity in the matter. Ambrose was as astonishingly prolific as he was because he was masterful at working with professional researchers and others -- his wife, Moira, and their five children all played roles in gathering, culling and arranging material in various of his books. He labored often 10 hours a day, sometimes seven days a week, and apparently enjoyed every minute of it. Late in his very successful career, this operation became a virtual book factory. My hunch is he got sloppy about quotation marks.

In racial harmony and justice, in women's rights, in other fundamental areas of freedom and fairness, Ambrose finds enormous progress in the U.S. through his entire life. Approaching death, he was ebulliently a happy man. This book is provocative and exciting. At times, Ambrose rambles, but for the most part his prose is clean, clearly stated. It is an entirely entertaining exploration of bits of American history, interlaced with reflections of an indomitably curious mind. To read it is to be struck with the terrible tragedy of Ambrose's early death.