BING CROSBY 
Swinging on a Star: The War Years, 1940-1946
By Gary Giddins
Illustrated. 724 pp. Little, Brown & Company. $40.

Television viewers who grew up in the 1970s knew Bing Crosby as the grandfatherly singing star of wholesome family specials, tuned into by their parents. Crosby was pipe-smoking, unruffled and witty, much like Father O’Malley, the Catholic priest he had played in two oft-rerun films, “Going My Way” and “The Bells of St. Mary’s.” By his side were his smiling wife and their model children, none of whom an even vaguely countercultural youth would have wanted to sit next to in the school cafeteria.

Since his music was not theirs, newer generations had no way to know that Crosby had not only changed the course of American popular singing, he had helped create it. It was he who, more than any other vocalist, had freed that art from its turn-of-the-century stiffness and transformed it into conversation. Drawing on black influences, he made pop songs swing, while treating a new invention, the microphone, as if it were a friend’s ear. Without him, Frank Sinatra, Peggy Lee, Dinah Shore, Dean Martin and countless other intimate singers could never have happened. A workhorse, he turned out a staggering number of recordings (including dozens of No. 1 hits) as well as films, radio shows and personal appearances. Whatever he did seemed off-the-cuff and effortless.

For all that, his reputation hasn’t much endured. He lacked the qualities that have made Sinatra eternally seductive: coolness, sex appeal, danger, risk and a singing style that opened a window into his hard living and emotional extremes.

Crosby had a far different job. With calm reassurance, he shepherded America through the Depression and World War II, then became a symbol of postwar domestic stability. Crosby applied his soothing baritone to love songs, folk songs, Irish songs, Hawaiian songs, country songs — he sang almost everything and revealed almost nothing. His 1953 memoir, “Call Me Lucky,” upholds the blithe facade. He seemed trapped in it.

Then, in 1983, six years after Crosby’s death, his oldest son, Gary, wrote his own book, “Going My Own Way” (with Ross Firestone). In it, he portrays the singer as a monstrous disciplinarian for whom beatings and belittlement were the answers to every filial problem. Gary had become an alcoholic; later in life, two of his brothers, Lindsay and Dennis, shot themselves in the head.

Not everyone was surprised. Many who had known Crosby remembered him as cold. In his last television appearances he stares out glumly with eyes of stone, perhaps weary of the role he’d had to play for 40 years.

All this is a biographer’s feast. But with a faded titan like Crosby, should one aim for a single, reader-friendly volume that might attract more than just die-hard fans? Or do the achievements demand a multivolume magnum opus, such as John Richardson is writing on Picasso and Robert Caro on Lyndon B. Johnson? And if a writer is enraptured enough to go that route, what to do when there’s lots of personal unpleasantness to address?

Crosby’s biographer Gary Giddins had choices to make. A formidable scholar of jazz and popular song, Giddins is certainly the man for the job. He spent 30 years as a Village Voice columnist. His journalism and his books about Charlie Parker and Louis Armstrong have won him scores of awards.

In 2001 he released the 700-plus-page “Bing Crosby: A Pocketful of Dreams — The Early Years, 1903-1940.” Now comes the comparably sized “Bing Crosby: Swinging on a Star — The War Years, 1940-1946.” It’s easy to see why Volume 2 took him so long. As before, Giddins researched a mountain of material to the max, and he lays his findings out with impressive clarity. At the start of the book, Crosby, 37, is America’s greatest star, a “national security blanket” whose role is about to grow as war approaches. Crosby’s weekly radio series, “Kraft Music Hall,” had made his voice as welcome in the American living room as Franklin Roosevelt’s. Once war was declared, the star took to the road to entertain the troops. The “Road” movies, his series of slapstick travelogues with Bob Hope, provided goofy escapist fun for the folks back home. In contrast, Crosby’s Oscar-winning portrayal of warm, wise Father O’Malley gave the Catholic Church its best P.R.

He tended his image carefully. “My private life is just like the private life of any other middle-class American family,” he declared. Crosby’s wife was Dixie Lee, a winsome songbird who had traded her career (and her peroxide-blond hair) for motherhood. On the air, Crosby depicted their four sons as adorable scamps. In truth, Dixie was a hopeless and nasty drunk, while Crosby, aided by his wife, doled out harsh corporal punishment to keep the boys in line. Gary had it the worst; aside from the beatings, his father humiliated him for a perceived weight problem, calling him Lardass and Bucket Butt. “Bing’s attempt to eradicate a sense of specialness and privilege in his sons,” as Giddins terms it, was undercut by the fact that they were Hollywood kids, trotted out as needed for show.

Giddins guides us past these minefields in brisk, lucid prose, as smoothly controlled as a Crosby performance. His scholarship and thoroughness earn the highest marks. But Crosby’s inner life is left mostly to the imagination. Perhaps few people understood it; he seems to have rarely dropped his mask, except to family. Giddins notes, but just in passing, “the undertow of loss and fear, the threat of unremitting loneliness” in many of Crosby’s song selections. Mary Martin, his co-star in the 1940 film “Rhythm on the River,” recalled Crosby as “absolutely terrified of any love scenes, any close-ups, any kissing.” According to the family friend Jean Stevens, Crosby had “no way to show his affection at all, never hugging the children for fear of spoiling them.”

But the why is unexplored. One can only imagine how Crosby felt when he visited Cardinal Francis Spellman to ask for counsel: He was thinking of divorcing Dixie and marrying the actress Joan Caulfield, with whom he was having an affair. “Bing,” the cardinal warned, “you are Father O’Malley, and under no circumstances can Father O’Malley get a divorce.”

Such material is moving, but there’s not much of it. Giddins seems more comfortable examining the career. He shines in his discussion of minstrelsy in film and its garish presence in the Crosby movie “Dixie.” The perils and drudgery of U.S.O. touring come to life. And Giddins tells us a lot about how Crosby and the director Leo McCarey jointly fashioned the Crosby-like character of O’Malley.

But the immensity of detail can be overwhelming. Pages and pages of historical context; sprawling lists of figures, song titles and names; letters quoted in near-entirety — all of this invites skimming.

How many more volumes would Giddins need to cover Crosby’s remaining 31 years? They include the singer’s entire television career, about 20 more films (including three of his best-remembered ones, “The Country Girl,” “White Christmas” and “High Society”); a more serene second marriage and family life; and his final concert years, when it was just Bing, face to face with his audience. As the work thins out and the frail humanity emerges, Giddins may face his greatest challenge.