In 1960, before his astonishingly swift ascendance to literary fame, Jorge Luis Borges must have seemed an unlikely candidate for the unofficial title of World's Most Influential Fiction Writer.

		"BORGES, A LIFE" By Edwin Williamson Viking ($29.95)

Borges, born in 1899, seldom ventured far from his home in Buenos Aires. When he left Argentina to lecture at the University of Texas in 1961, it was the first time, says Edwin Williamson in his richly detailed biography, that the writer "had set foot outside the region of the River Plat since 1924."

Frail, balding and timid, Borges had written practically nothing of interest, even to Buenos Aires literary salons, since 1953. In truth, he hadn't written much before then at all.

His oeuvre consisted of a few darkly elegant poems, some provocative and idiosyncratic essays and a few slim volumes of what he called "ficciones" that even his most ardent admirers were unsure should be placed under the category of fiction or nonfiction.

Then, in 1961, Borges' life and Western literature were both changed forever. As Williamson phrases it, "a stroke of luck that came like a bolt from the blue" arrived in the form of the International Publishers Prize.

With such dazzling short works as "The Aleph," "The Circular Ruins," "The South," "The Dead Man, "Borges and I" and, most famously, "Pierre Menard, Author of 'Don Quixote,' " Borges redefined and redirected the course of fiction.

Within 10 years he had become the most influential fiction writer since James Joyce, having wide effect, in the words of the great Italian novelist Italo Calvino, "on creative writing, on literary tastes and on the idea of literature itself."

He was read avidly by college students, lionized by rock stars and, on one bizarre occasion, at a reading, mobbed by (or so reported the Argentinean press) "an audience of London hippies ... hairy, disheveled, wildly enthusiastic young people."

William-son, a Spanish scholar at Oxford and author of "The Penguin History of Latin America," is the first to map Borges' strange odyssey. He was raised by an uncaring father and domineering mother who would continue to exercise an unhealthy control over his life till Borges was in his 60s. All his life, writes Williamson, "he fell for women who would be unacceptable to mother, either because they came from an inferior social class or because they did not meet the high standards of respectability required by Dona Leonor."

He was ill much of his childhood and held out of school. He had few friends and spent most of his formative years wandering in his father's enormous library, which included lurid tales of Argentina's bloodthirsty frontier bandits.

By the time he turned 20, he was fluent in English and French, with a rudimentary knowledge of Latin and Hebrew. He dabbled in several literary forms, settling on none, and contributed to several local avant-garde publications.

None of this helped him earn a living. He disgraced his father by taking humbling jobs such as clerk in the Buenos Aires Municipal Library. One day a coworker stumbled on a biographical reference to a little known but critically acclaimed writer named Jorge Luis Borges and pointed out the amazing coincidence of the name.

Gradually, with painful slowness, his reputation filtered out to European intellectuals on the lookout for new currents from the world's literary suburbs. When the great boom in Latin letters finally came in the 1970s, Borges, the first Latin writer who most non-Latins had ever heard of, was at the crest.

Because he labored for most of his life in obscurity and opposed the government of the dictator Juan Peron, Borges' life is nearly as labyrinthine as his fictions. Williamson has successfully weaved a precarious path between authorized and uncompromised biography, and in the process has given us what will surely be regarded for many years as a definitive one.