Winston Churchill was an old-fashioned hero — majestic, eloquent, effusive, addicted to drama. He had an enormous personality but a simplistic outlook: He saw the past as a collection of heroic tales immune to analysis. The latest biography of Churchill has much in common with the man himself. “The Last Lion” is a majestic saga in the Victorian style — vivid, articulate, beautifully composed, grand in scope but thin on introspection. The similarity goes further: Rather like Churchill, this book is very fat. How strange, then, that such a corpulent tome has so much missing.

“The Last Lion,” the third installment of William Manchester’s biography of Churchill, starts in 1940, when he became prime minister, and ends with his death in 1965. In truth, however, it’s a book about Churchill’s war. Manchester had essentially completed the research by 1998, but then ill health made writing impossible. Before he died in 2004, he handed the book over to his friend Paul Reid, a journalist. At the time, only a tenth of the more than 1,000 pages had been written.

Reid has done a superb job of creating a book that reads like Manchester. As he writes, his mentor “was not an academic. He was a storyteller who made history accessible by masterful use of the dramatist’s tools.” “The Last Lion” fits that mold: This biography has the dramatic punch of a great novel. Yet it is strange to find a new book that seems so old — rather like an ancient butterfly sealed in amber. This is because it was researched in the 1980s but written decades later. Unfortunately, much has been discovered in the interim, by historians such as Paul Addison, Peter Hennessey, Angus Calder, Roy Jenkins, Max Hastings and others. Reid claims that he updated the research he inherited from Manchester, but there’s little evidence of that.

“The Last Lion” is very good on Churchill the hero. His heroic phase came when England stood alone against Hitler, a period that lasted until mid-June 1941. This was the “supreme chapter in his life” — roughly 400 days that he called “the most splendid . . . year in our long . . . English story.” There was an element of serendipity to that period, perfectly summarized by the psychiatrist Anthony Storr in an article first published in 1973. According to Storr, at that time, Churchill’s “inner world of make believe . . . coincided with the facts of external reality in a way that rarely happens to any man.” In other words, Churchill got to be the hero he had always dreamed of being but also precisely the hero that the British demanded. He was able to guide Britain through its darkest hour because he was steeped in English myth. A more rational man might have decided that all was lost.

After the Soviet Union and the United States entered the war, the context changed radically, and singular valor diminished in importance. Victory for the Allied powers became inevitable, the only uncertainty being the element of time. During this period, political issues (domestic and foreign) became more important than simple courageous leadership. As a result, Churchill’s knightly armor grew tarnished because he was ill-equipped to deal with the political complexity of that world. He did not, for instance, really understand the relationship with the United States, wrongly assuming that the Americans would keep British best interests in mind. Nor did he remotely understand how the atom bomb changed not only warfare but international relations.

Even more seriously, he did not comprehend the way the British people had changed because of their struggle. Industry was nationalized, food rationed and labor controlled. Britain became a socialist nation in all but name. Far from resisting these changes, the British welcomed them because a fairer society evolved. Burdens were shared and rewards equitably distributed. Despite shortages, health actually improved. No wonder, then, that the people saw the wartime context as a model for the New Jerusalem they hoped to build after victory.

That explains the massive defeat of Churchill’s Conservative Party at the election in July 1945. Outsiders often judge that election a betrayal, as if Churchill deserved to remain prime minister simply out of gratitude. Yet for many Britons, then and now, that election was a proud moment when, rather than looking backward, they had the courage to imagine a glorious future. That future did not include Churchill. The attributes that rendered him perfect in 1940 rendered him irrelevant in 1945.

These nuances are missing from “The Last Lion.” The book reads like a wartime blockbuster by Herman Wouk, when what the subject demands is Shakespearean subtlety. One example of the book’s superficiality is its discussion of the destruction of Dresden. The authors present that action as just another episode in a long bombing campaign, yet historians now generally accept that it was something uniquely vicious. Interpretations vary: It was perhaps an act of spite, an attempt to intimidate the Soviets or a manifestation of Churchill’s febrile bellicosity.

It was also a bit cowardly. Prior to the bombing, Churchill asked his air minister, Archibald Sinclair, for his plans for “basting the Germans in their retreat.” When Sinclair duly supplied a sensible plan for harassing that withdrawal, Churchill angrily demanded something altogether more ferocious. The result was the Dresden firestorm, an action without real purpose beyond vindictiveness. Yet when a moral backlash resulted, Churchill blamed Sinclair, chastising him for “bombing German cities simply for the sake of increasing the terror.”

Manchester and Reid neglect these details of the bombing. The real Dresden story is much more dramatic, sordid and interesting than the one they recount in “The Last Lion.” The same can be said for all of Churchill’s war. The problem arises because the authors revere their subject too much, and reverence impedes good biography.

As an adventure story, this book is superb. It has tremendous pace, rich detail and immense drama. That is appropriate, since few characters are as huge as Churchill. But we need to move beyond the shining deeds of extraordinary heroes. Churchill becomes much more interesting when his flaws are admitted and his limitations exposed.

Gerard DeGroot is professor of history at the University of St. Andrews in Scotland and the author of “The Bomb: A Life.”


Winston Spencer Churchill:

Defender of the Realm, 1940-1965

By William Manchester and Paul Reid

Little, Brown. 1,182 pp. $40