Bing Crosby was not a rock-and-roll artist, but rock stars are still taking pages from his book.

Decades before the Beatles abandoned live performance, Crosby decided his touring life was through as he focused on shooting movies, doing radio shows, and of course making records. He was a multimedia star like none that had gone before, and helped show the likes of Elvis how to use a microphone in the intimate style called "crooning."

Four decades after his death and seven decades after his career peak, Crosby is probably more widely heard today than any other vocal star of the pre-rock era — even Frank Sinatra. It's easy to imagine a Crosby career where he'd be remembered by classic movie buffs and war historians, but where the average 21st-century American couldn't instantly identify his voice.

The reason Crosby remains instantly recognizable today: Christmas. The story of how the Tacoma native named Harry Lillis Crosby Jr. (he got his lifelong nickname at age six, from a newspaper column he loved called "The Bingville Bugle") became the ubiquitous "Voice of Christmas" starts in a newly published volume of Gary Giddins's biography.

A Pocketful of Dreams — The Early Years came out in 2001, spanning the first 37 years of Crosby's life (1903-40). The new book, Swinging On a Star — The War Years, only covers six years (1940-46), but they were pivotal years for Crosby and the nation.

As the 1940s began, Crosby was already a huge star. Having risen from vaudeville entertainment to movie and radio fame, he lived in a fancy house with his wife, a starlet in her own right named Dixie Lee, and their four boys. People were itching to see more of Crosby alongside his new co-star, Bob Hope.

There were troubles, though, both in the world and at home. A globe-spanning conflict was brewing, and Lee — having convinced Crosby to kick the bottle — was now succumbing to severe alcoholism herself. Crosby was often away making movies, and the couple's children would grow up to have a range of memories of their parents. Oldest son Gary would eventually publish a widely-discussed book painting his father as an abusive monster; the other children didn't share that strong view, but Crosby felt the need to be the family disciplinarian, and corporal punishment was routine.

In brief, the story of The War Years is the story of how Crosby went from a hugely popular entertainer to an American icon, indelibly associated with stability and comfort at a tumultuous time. He was a master of then-contemporary pop, priding himself on being able to sing anything from hymns to jazz to comic numbers. (Flexibility and offhand appeal, not personal revelation, were his trademarks. As James Gavins puts it, "he sang almost everything and revealed almost nothing.") Many of his most famous wartime recordings were made with Minnesota natives the Andrews Sisters, who struggled not to laugh at Crosby's expert improvisations.

He also continued to shine as a film star. In addition to his "Road Movies" with Hope (Road to Zanzibar, Road to Morocco, etc.), he won an Oscar for his performance as a young priest in Going My Way. It was his movie career that made him the King of Christmas: in the 1942 movie Holiday Inn, he sang Irving Berlin's "White Christmas," and it became his biggest hit.

You're more likely to have seen the 1954 film that centers on that song than the 1942 original, in part because Holiday Inn includes one of multiple instances when Crosby appeared onscreen in blackface. Still a mainstream trope in the 1940s, blackface minstrelsy featuring both white and black performers was practiced onscreen and on stage; while Crosby's generation would be the one to leave blackface behind, the fact is, that didn't happen until the postwar period. Even White Christmas includes a minstrel number, without makeup.

As the war approached its bloody end, Crosby — along with Hope, Sinatra, Dinah Shore, Fred Astaire, and many others — joined in USO tours to entertain the troops. Those tours formed a lasting pillar of Crosby's appeal, as dramatized in White Christmas. While Crosby didn't actually fight in the war, he did perform so close to the action that troops would be called out of his audiences to go fight ("the only time an audience walked out on Bing Crosby," read one headline).

On one occasion, Crosby's driver accidentally drove past the front and realized he was in enemy-occupied territory before turning around and hustling back to safety. When they arrived at the Allied base and Crosby told an officer the name of the town they'd driven through, the officer said in astonishment that the town was in German hands. "Well," quipped Bing, "we had it for two minutes."

The most moving revelation of Giddens's detailed accounts is that the scene depicted in White Christmas, with Crosby crooning "White Christmas" to exhausted troops on a makeshift stage with gunfire erupting all around, wasn't too far from the truth. No wonder the song earned a unique place in American culture.

Crosby's voice was even deployed in a charm offensive, broadcast in German to stir the hearts of those who might help bring about an end of the Nazi reign. A Variety journalist gave Crosby a new moniker when he wrote, "While Hitler is fooling around with buzz-bombs and pick-a-pack planes, we're hurling a real secret weapon at Germany. Der Bingle is what the Germans call it."