Callie Russel Porter, born in Indian Creek, Texas, was the fourth of five children of Harrison Boone Porter and Alice (Jones) Porter. Her family tree can be traced back to American frontiersman Daniel Boone, a heritage of which she was proud.
In 1892, when Porter was two years old, Porter's mother died two months after giving birth to her last child. Porter's father took his four surviving children (an older brother had died in infancy) to live with his mother, Catherine Ann Porter, in Kyle, Texas. The depth of her grandmother's influence can be inferred from Porter's later adoption of her name. Her grandmother died while taking eleven-year-old Callie to visit relatives in Marfa, Texas.
After her grandmother's death, the family lived in several towns in Texas and Louisiana, staying with relatives or living in rented rooms. She was enrolled in free schools wherever the family was living, and for a year in 1904 she attended the Thomas School, a private Methodist school in San Antonio, Texas. This was her only formal education beyond grammar school.
In 1906, at age sixteen, Porter left home and married John Henry Koontz, the son of a wealthy Texas ranching family, and subsequently converted to Koontz's religion, Roman Catholicism. Koontz was physically abusive; once while drunk, he threw her down the stairs, breaking her ankle.
In 1914 she escaped to Chicago, where she worked briefly as an extra in movies. She then returned to Texas and worked the small town circuit as an actress and singer, divorcing Koontz in 1915. As part of her divorce decree, she asked that her name be changed to Katherine Anne Porter.
Also in 1915, she was diagnosed with tuberculosis and spent the following two years in sanatoria, where she decided to become a writer. It was discovered during that time, however, that she had bronchitis, not TB. In 1917, she began writing for the Fort Worth Critic, critiquing dramas, and writing society gossip. In 1918, she wrote for the Rocky Mountain News in Denver, Colorado. In the same year, Katherine almost died in Denver during the influenza pandemic (the Spanish flu). When she was discharged from the hospital months later, she was frail and completely bald. When her hair finally grew back, it was white, and remained that color for the rest of her life. Her experiences during treatment provided the background for her short novel Pale Horse, Pale Rider.
In 1919, Porter moved to Greenwich Village in New York City and made her living ghost writing, writing children's stories and doing publicity work for a motion picture company. The year in New York City had a politically radicalizing effect on her, and in 1920, she went to work for a magazine publisher in Mexico, where she became acquainted with members of the Mexican leftist movement, including Diego Rivera.
Eventually, however, Porter became disillusioned with the revolutionary movement and its leaders. During this period, she also became intensely critical of religion and remained so until the last decade of her life when she again embraced the Roman Catholic Church.
Between 1920 and 1930, Porter traveled back and forth between Mexico and New York City and began publishing short stories and essays. In 1930, she published her first short story collection, Flowering Judas and Other Stories. An expanded edition of this collection was published in 1935 and received such critical acclaim that it alone virtually assured her place in American literature.
In 1926, Porter married Ernest Stock and lived briefly in Connecticut before divorcing him in 1927. Some suggest that Porter suffered several miscarriages, at least one stillbirth between 1910 and 1926, and an abortion, and after contracting gonorrhea from Stock, that she had a hysterectomy in 1927, ending her hopes of ever having a child. Yet Porter's letters to her lovers suggest that she still intimated her menstruation after this supposed hysterectomy in 1927. As she once confided to a friend, "I have lost children in all the ways one can."
During the 1930s, Porter spent several years in Europe during which she continued to publish short stories. In 1930, she married Eugene Pressley, a writer thirteen years her junior. In 1938, upon returning from Europe, she divorced Pressley and married Albert Russel Erskine, Jr., a graduate student who was twenty years younger. He reportedly divorced her in 1942 after discovering her real age. She never remarried.
Between 1948 and 1958, Porter taught at Stanford University, the University of Michigan and the University of Texas, where her unconventional manner of teaching made her popular with students. In 1962, she published her only novel, Ship of Fools, which was the best-selling novel in America for that year; its success finally gave her financial security (she reportedly sold the film rights for $400,000).
Despite Porter's claim that after the publication of Ship of Fools she would not win any more prizes in America, in 1966 she was awarded the Pulitzer Prize and the National Book Award for The Collected Stories of Katherine Anne Porter, and that year was also appointed to the American Academy of Arts and Letters.
In 1977, Porter published The Never-Ending Wrong, an account of the notorious trial and execution of Sacco and Vanzetti, which she had protested fifty years earlier. Porter died in Silver Spring, Maryland on September 18, 1980, at the age of 90, and her ashes were buried next to her mother at Indian Creek Cemetery in Texas.