In the history of American popular music a special if somewhat ambiguous place is occupied by the man who was born Nathaniel Adams Coles but is known, almost universally, as Nat King Cole -- with no quotes or parentheses, if you please, around the King. For about a quarter-century, from the late war years until his death in 1965 at the age of 45, he was a hugely successful singer of ballads and novelty songs whose audience rivaled Frank Sinatra's, and as a jazz pianist he won the intense admiration of musicians and critics; yet he was a black performer in a white world, and invariably his successes were compromised and diminished by questions of race.

If anything, Cole's story provides instructive evidence of how far we have progressed in racial affairs. Two decades after his death no one seems to find it especially remarkable that countless millions of teen-aged white girls writhe in ecstasy over the overtly erotic tunes of Michael Jackson and Prince, both of whom are black. But in the '40s and '50s it was considered remarkable indeed -- in many quarters it was considered shocking and outrageous -- that Cole sang love songs and that white couples danced and romanced to them.

Cole was no pioneer, but he was ahead of his time by a few years and as a result the central theme of his story is not his music but his race. Of the excellence of the former there is no question. He began as a jazz pianist, scraping out a living in Chicago clubs; his style was influenced by the great Earl Hines, as he readily admitted, but quickly evolved into one that was distinctly his own. His singing was similarly distinctive; his throaty voice, caressing each word of a song, was immediately recognizable. The group that he led for most of his career, the King Cole Trio, was one of the best in jazz and/or pop music -- and it's no small tribute to his skills that he occupied both worlds with equal comfort.

He did so, though, to the discomfort of some of his listeners. The more successful he became, the more he turned to lushly orchestrated arrangements featuring string accompaniment -- arrangements that caused his admirers among jazz followers to accuse him of "commercialization" and "selling out." His response did not satisfy them, but it made sense: "Listen. I'm a business man. I work for business people. The kind of thing they say is: Now we've sold a lot of records, let's sell some more. I try to appease both sides but it's tough." Not surprisingly, more often than not he chose to appease the side where the money was: the world of popular music, the white world.

He got the money, but he does not seem to have gotten much peace of mind. Whites paid him, but in many places they wouldn't let him sleep in their hotels or eat in the cabarets where he sang; in 1956, in Birmingham, a gang of whites physically attacked him on stage in an unsuccessful attempt to abduct him. To this as to most other racial incidents he responded with public equanimity (though "privately, he was angry and frightened"), which only aroused the anger of black civil rights activists, who called him an Uncle Tom.

He wasn't: "Cole was a quiet man who preferred to avoid controversy and who was very realistic in his assessment of the boundaries beyond which he, as a black, could not go, no matter how many of his recordings reached number one on the popular charts." A good case can be made, in fact, that Cole's acceptance of the realities he faced was the equivalent of Jackie Robinson's refusal to respond to the race-baiting he encountered from baseball players and fans -- a courageous, and strategically effective, weapon that helped inch blacks toward the main currents of American society. The clarity of hindsight suggests that his actions did not demean him, but ennobled him.

He seems, as portrayed by James Haskins and Kathleen Benson, to have been an uncommonly decent man who probably was shortchanged in the happiness department. Not merely was he poised for his entire adult life on the razor's edge between the worlds of black and white, but his domestic life seems to have left a good deal to be desired. His second marriage, though it began well enough and his wife had a positive influence on his career, deteriorated in his last years and, according to several witnesses, almost certainly would have ended had he not been killed by lung cancer. He seems to have been devoted to his several children, both biological and adopted, but his schedule permitted him little time with them; probably he was as frustrated and saddened by this as they were.

Because Cole was so intensely private, he ultimately eludes his biographers. Haskins and Benson try hard, but for the most part what they are able to come up with is a long and somewhat numbing chronicle of concert engagements and recording dates in which Cole the man tends to get lost. This is unfortunate, but since his hundreds of wonderful recordings are still abundantly available, it probably is not very important.