THE NAME Mary Roberts Rinehart means little to the contemporary reading audience, yet in her heyday (1908 to the late 1930s), as Jan Cohn tells us in this well-researched, well-organized biography, she was a literary celebrity with few rivals. In her position as a female exemplar to the nation, she was a nurse who became a doctor's wife, bore three sons, "wrote more best-selling novels . . . over a longer period than almost any other American writer," had two hits plays running simultaneously on Broadway, and, acting as a war correspondent, was the first journalist -- man or woman -- to reach the front during World War I.

In addition, Rinehart was an honorary Blackfeet Indian (they renamed her "Running Eagle"), covered the political conventions of 1916, lived in a haunted house, unearthed German spies, went public with a mastectomy (in 1947), and kept up a continual stream of magazine articles and interviews in which she reminded her fans that she was foremost a wife and mother, and so should they be.

What changes the life of Mary Ella Roberts, born in 1976, spanned! It wad during the year of her birth that Custer made his last stand, and it was also the year that Alexander Graham Bell unveiled the telephone. Ulysses S. Grant was in the White House, and, of course, Victoria ruled England and the Empire. What seer could have foreseen that the eldest daughter of a failed saleman (he committed suicide in 1895, when Mary was in nursing school) would dine with presidents, be the first American woman offered an ambassadorial appointment, pay over $46,000 in federal taxes in 1922, and be interviewed on television by Jerry Lewis, two years before her death in 1958? Mary Roberts Rinehart cherished her remarkable success story, and, tempering her affection for subject with objectivity, Jan Cohn does the same.

Although Rinehart's most popular novels -- The Circular Staircase, The Man in Lower 10, The Breaking Point, Lost Ecstasy, The Door -- have been almost steadily in print since she died, it is not really as an author that Cohn "reclaims" her. Rather, her interest in Rinehart stems from the fascination of what Cohn terms "the Rinehart myth: the successful writer born out of financial need, family responsibility, and pure chance." Taking this "myth" under advisement (Rinehart herself propagated it in her 1931 autobiography, My Story , swinging behind it all the weight she has accumulated as America's favorite matron-of letters), Cohn goes on to investigate Rinehart as personality and personage. She attempts to capture her as a popular artist whose greatest creation was not her body of work but her own existence, and she succeeds, not brilliantly but sturdily, professionally. We see how Rinehart mistrusted her early "need to become someone, to achieve something" and that "out of the central disharmony of her life, the profound ambivalence with which she enacted her roles, as writer and as wife and mother, she constructed an apologia, explaining her career to her audience, her family -- even to herself.

In other words, Rinehart was too much the product of her late 19th-century upbringing to savor without guilt (and elaborate systems for masking her independence from her family) the rewards, excitement and glamor her talents brought her. The figure Rinehart presented to her public was one she believed in utterly: the Writer as Womanly Woman, somehow putting home and hearth first, even if not always there.

One cannot fault Cohn's sense of era and place, she paints a fine portrait of that time when the upper-middle class smugly ruled the country from fortified positions in New York, Boston, Washington and Bar Harbor; when George Horace Lorimer held sway despotically over The Saturday Evening Post which in turn, with contributors like Mary Roberts Rinehart, kept America in its literary grip. However, it is unfortunate that Cohn has either not known about or chosen to ignore some details -- espectially about detective fiction -- which would have enhanced her material.

The most important of these omissions is Cohn's neglect of a similar but less important and romances, Anna Katherine Green. Green was obviously familiar to Rinehart since one of the older writer's books, picked at random from a shelf, inspired Rinehart to submit her first novel to the same publisher. In a lengthy description and analysis of the originally of Miss Rachel Innes -- a spinster sleuth who appears in Rinehart's first hit, The Circular Staircase (1980) -- Cohn seemingly is unaware that a Green detective, Miss Amelia Butterworth (who made her debut in 1897), established the prototype for the elderly woman always game for a mystery, delighting in adventure, unabashedly curious. Cohn also foregoes the chance to point out some curious parallels between Rinehart and Arthur Conan Doyle and also Agatha Christie, although each gets a mention. It is not that Cohn has made an inappropriate choice in emphasizing Rinehart as a creature of American popular culture, rather than as a doyenne of the mystery; it is only that for some readers these touches will be noticeably lacking.