The death last week of Eudora Welty marked the passing of a great American writer. It also marked the passing of the last of a remarkable group of US southern writers that included Flannery O'Connor, Carson McCullers and William Faulkner, Welty's hero and fellow Mississippian, all of whom died in the 1960s, as well as Peter Taylor of Tennessee, who survived until 1994.

It is exactly a year since the death of the Midwesterner Bill Maxwell, to whom Welty had dedicated The Ponder Heart in 1953, and it could be argued that only Saul Bellow, who is now 86, the somewhat younger John Updike and, to a far lesser though more controversial extent, Norman Mailer and Gore Vidal remain of the 20th century writers who helped to establish US literature as an international force.

Welty, who had turned 92 in April, understood - and respected - better than most writers the singularity of people, their individuality, their essential oddness. Unlike many storytellers, even her most gifted fellow southerners, Welty portrayed eccentrics - such as the Why I Live At The P.O. - - brilliantly, compassionately and without resorting to grotesquerie.

Her gift has been described as quiet, but this falls far short of her achievement. It was certainly subtle, but she is a versatile, diverse artist with immense comic powers, as demonstrated throughout The Ponder Heart and the often burlesque domestic saga Losing Battles, from 1970.

This big novel of voices, spanning two hectic days in a family reunion and years of memories, showcases one of her abiding strengths: her phenomenal ear for speech, particularly the colourful, teasing vernacular of the South. It would be an injustice, though, not also to acknowledge her range and technical virtuosity.

Consider a story as terrifying as Where Is The Voice Coming From?, a brutal monologue allegedly delivered by the crazed white killer of Medgar Evers, a black man. Welty tried to capture the mind rather than the identity of the murderer - and does. Then look at the extraordinarily poignant and atmospheric No Place For You, My Love, in which two northern strangers who have met across a luncheon table in New Orleans go for a drive into the Deep South, or the hilariously fluid and unreliable narrative provided by Edna Earle in the Ponder Heart.

Welty's second book, and first novel, the Robber Bridegroom from 1942, is a surreally inventive, quicksilver variation of the European fairy tale that leaves Angela Carter, a later experimentalist with the genre, upstaged by its virtuosity.

Delta Wedding, published in 1946 and set in 1923, is about as graceful and nuanced a portrait of southern life - seen through the eyes of Laura, a nine-year-old guest - as could be imagined. Welty's fiction is more diverse than might be suspected of one so committed to conveying a sense of place. Though a personal writer, she is emphatically non-autobiographical.

Yet her masterpiece, The Optimist's Daughter, which began life as a shorter piece in the New Yorker and won the Pulitzer Prize for Fiction in 1973, draws on her relationship with her parents. Few novelists have matched Welty's depiction of the pain of Laurel, the widowed daughter of the title, as she finally confronts her family past.

The stark beauty of the narrative in the late sequences during which Laurel explores her old family home before the return of her now dead father's despised second wife, Wanda Fay, is heartbreaking. It also counters Laurel's stiff resentment of her unlikely stepmother and the black comedy of the funeral, as Wanda Fay's vulgar family, which she had denied having, come to cheer on their little girl's expensive burial of her husband.

Such a deeply felt novel almost renders an autobiography irrelevant. Yet Welty wrote one. One Writer's Beginnings, from 1984, is not the most confessional of memoirs, but it is among the most gracious and informed accounts of the development of a literary consciousness. It is difficult to pin down this most natural of storytellers, who embraced the regionalist label, never made a mystery of herself or her art, wrote some fine criticism and yet remains elusive.

There is even the fact that this most southern of writers could only just claim to be a southerner. Her father was from Ohio, while her mother was from West , culturally, quite part of the South.

But Welty decided to embrace that culture, and became part of it despite time spent in Europe and New York, a city she visited most years. She was friendly with Elizabeth Bowen, to whom she dedicated her Irish story, The Bride Of The Innisfallen.

Yet Welty's literary terrain was always the South, not least because people tended to stay there, and her fiction celebrates continuities of family and place. She saw the South as more than her inspiration: it was her source of knowledge.

Born in Jackson, Mississippi, in 1909, Eudora Alice was the eldest of three and, years later, would dedicate Losing Battles to her brothers, both of whom were dead before it was published. Her father had moved to Jackson to work for an insurance company of which he later became director.

Like his wife, he had been a teacher. This is significant. Schoolteachers such as Julia Mortimer in Losing Battles are visionaries, often outsiders, like Gloria in the same novel.

The young Welty grew up in a home where books were loved and discussed and the Bible was revered. At 16, she went to Mississippi State College for Women and, two years later, transferred to the University of Wisconsin, from which she graduated at the age of 20.

She spent a year at Columbia University Graduate School of Business, studying advertising, and returned to the family home in Jackson for the rest of her life, though not in time for her father's death. She lived with her mother, who died, after a long illness, in 1966. Welty never married and had no children.

Having worked for local newspapers, she at one time had a social column; for radio, she did her bit for President Franklin D. Roosevelt's New Deal as publicity agent for the Works Progress Administration. She recorded her travels and interviews through poverty-stricken Mississippi with photographs that were eventually published in 1971, as One Time, One Place: Mississippi In The Depression, A Snapshot Album, although they had also been exhibited in New York in 1936.

By then, Welty had begun writing fiction. Death Of A Travelling Salesman, her first published story, also appeared that year in the Southern Review, then edited by the poet Robert Penn Warren. Her links with the journal endured, as did her friendship with the Texan writer Katherine Anne Porter, who wrote the introduction to Welty's first collection, A Curtain Of Green, from 1941.

While Welty was modest about her work, she was not coy. Her intelligence always shone through. The humour in her fiction can be earthy and is often marked by a skilful use of mistaken identities and coincidences. It's a comic device she used to dazzling effect in The Ponder Heart, in which the self-destructively eccentric Uncle Daniel is wrongly accused of killing his hysterical wife, and, of course, in Losing Battles.

Although this subtle, even deceptively complex poet of place is far less a chronicler of the Old South than some critics appear to suggest, for all her independence, she conveys some belief in the role and power of southern womanhood, especially motherhood, that is more traditional than she may have intended. This makes her use of the southern Gothic, as well as the fairy-tale genre and its sexual undertones of female fear of male sexuality, in The Robber Bridegroom all the more interesting - and true to Welty's ironic world view.

Delta Wedding could be viewed, and has been, as a celebration of the traditional domestic sphere of women's lives. It may even be seen as a pastoral hymn to fertility. Yet the story stands beyond whatever political context a later generation of gender-based literary critics may choose to impose upon the text. Welty's story of the Fairchild clan is intended to portray a family anxious to seek a retreat from the modern world into a past that appears more attractive.

Any number of stories from her five collections, including The Wide Net, from 1943, The Leaning Tower, from 1944, and The Bride Of The Innisfallen, from 1955, with its number of European stories, testify to her mastery of the form.

An admirer of Jane Austen, Virginia Woolf, Katherine Mansfield and Henry Green, Welty was particularly devoted to Chekhov's understanding, humour and studies of people intently talking with no one listening. She saw him as remaining "close to today's world and very close to the South".

At her finest, in the Optimist's Daughter and in many of her stories, she makes clear that her literary kindred spirit is none other than the great Russian master, whose humanity, feel for character and vision she shared.