The film American Fiction opens in a university classroom with Monk, played by Jeffrey Wright, teaching the literature of the American south. On a whiteboard is written “Flannery O’Connor” and the title of one of her short stories. A title that contains the N-word. When a white student objects, Monk, who is Black, tells her: “With all due respect, Brittany, I got over it, I’m pretty sure you can too.” The student walks out in tears.

American Fiction leaves it there but anyone provoked to learn more about O’Connor is in luck. Wildcat, an independent movie directed by Ethan Hawke and starring his daughter Maya Hawke, dips in and out of the life story and imagination of the novelist and short story writer who defined southern Gothic literature.

O’Connor never married, died from lupus aged 39 and, as her biographer puts it, has entered an “iffy” period because of her views on race. The Associated Press recently recounted a jokey conversation between Ethan and Maya about how difficult a biopic would have been to pitch to a major studio –

Maya: “We want to make a movie about an unfortunate-looking woman with lupus. She struggles with her faith and has no boyfriends.”

Ethan: “She’s a really brilliant writer but she’s completely unsuccessful.”

Maya: “Also recently her mild success has been completely disbarred and people are mostly interested in removing her from the canon these days. What do you think?”

Ethan: “Sounds like the makings of a commercial, hit movie!”

One likely viewer is the TV host and comedian Conan O’Brien, who studied O’Connor at Harvard University. He once remarked that when he first encountered her darkly witty oeuvre, he thought it must be the work of a bitter old alcoholic. He was amazed that it had come from the pen of a devout Catholic woman in the south.

She was born Mary Flannery O’Connor in Savannah, Georgia, in 1925, the only child of Edward O’Connor, an estate agent, and Regina Cline O’Connor. She later described herself as a “pigeon-toed child with a receding chin and a you-leave-me-alone-or-I’ll-bite-you complex”.

Janie Bragg, director of the Flannery O’Connor Childhood Home museum in Savannah, Georgia, describes O’Connor as a “quirky, imaginative kid” who used to read Edgar Allen Poe in the bathtub. “She was quite the oddball as a child,” she continues. “She would dress up her chickens and walk them around town on leashes in full handmade outfits. She was an only child so that was her way to express herself and entertain herself.”

In 1938, O’Connor’s father was diagnosed with lupus, a chronic disease that can cause inflammation and pain in any part of the body. It claimed his life in 1941, when O’Connor was just 15 years old.

She attended the Georgia State College for Women (now Georgia College & State University) then pursued graduate studies at the prestigious Iowa Writers’ Workshop, where she began to develop a distinctive voice and became close to the poet Robert Lowell.

But O’Connor herself became ill with lupus at 25, compelling her to move back to Georgia and live with her mother (played by Laura Linney in Wildcat) at a 500-acre farm in Milledgeville. She attended mass daily, tended to peacocks that roamed the property and focused on her writing. She once said: “I can, with one eye squinted, take it all as a blessing.”

Brad Gooch, author of Flannery: A Life of Flannery O’Connor, says by phone from New York: “She said somewhere that until she was 25 years old she was convinced that the life of her writing depended on her leaving home but, once she’s forced back, she discovers her material around her. It’s like a prodigal daughter story.

“She put a lot of gossip about Milledgeville in her work. She got characters’ names from the phone books and was also taking on topical issues of race, what was going on in the Catholic church and the Vatican that time. And you always have to laugh if you’re talking about Flannery O’Connor. Acid humour was a big part of her work.”

O’Connor wrote every morning with religious devotion. Gooch continues: “She has this convent-like schedule and she sticks to that. She did say she looked forward to writing, that it was like eating a filet mignon. All of her life she had a sense that it was her writing that she was living for.

“That was the purpose and meaning of her life and it was also what was keeping her alive. That was maybe a kind of magical thinking or magical religious spiritual thinking. The stories were what kept her going and were the last thing to go. She’s writing some great stories right into the final months.”

O’Connor never wanted to be pigeonholed as a “southern writer”. Jessica Hooten Wilson, author of Flannery O’Connor’s Why Do the Heathen Rage?, an exploration of O’Connor’s unfinished third novel, says: “She grew up in the south and was very saturated in it – if you think about the southern manners and hierarchy of classes and racism, she was in all of that in the 1920s and 30s in the south.

“But then she went away to Iowa, New York, Connecticut, and so when she returned home because of the lupus and was forced to stay in the south for the last 14 years of her life, she had this perspective that was both insider and outsider.”

Wilson, an academic at Pepperdine University, adds by phone from Malibu, California: “It allowed her to be critical of the racism that she knew she was a part of and participating in. I don’t think that a lot of the people around her had that critical lens. They had not left home the way she had. They had not been in integrated communities the way that Flannery had been in New York.

“That kind of vision that was opened up to her is what provided her work a more longstanding, universal vision that we can still read today, rather than if she had only been in the south and never left home and seen the south from the outside.”

O’Connor died in 1964. An obituary in the New York Times called her “one of the nation’s most promising writers”. She won the National Book Award posthumously in 1972. The literary world never got the chance to see what she might have done next.

Bragg reflects: “It’s tragic for us that we didn’t get more writings but she was also incredibly prolific in the 39 years that she had and getting sick deepened her writing in an interesting way. It’s a catch-22: it made her writing more interesting and it also served as quite the motivator to be the writer she wanted to be because she knew that she had a limited time.”

O’Connor’s body of work is full biting satire, vivid portrayals of the southern landscape and themes such as morality, faith and the grotesque. She nails Christian hypocrisy and depicts flawed characters grappling with existential questions.

Her debut novel, Wise Blood, about religious extremism in the deep south, was published in 1952 and later adapted into a film directed by John Huston. Her first collection of short stories, A Good Man Is Hard to Find, was published in 1953 to critical acclaim.

But in recent years O’Connor has come under scrutiny for racism in private correspondence and her treatment of race in her works. In May 1964, just before President Lyndon Johnson signed the Civil Rights Act, she wrote in a letter: “You know, I’m an integrationist by principle & a segregationist by taste anyway. I don’t like negroes. They all give me a pain and the more of them I see, the less and less I like them. Particularly the new kind.”

Bragg points out that O’Connor was born in 1925 in the deep south. “I don’t think that it should come as a surprise that she had views that we don’t agree with now. People pore over her writings, seemingly looking to dissect her to define her in one way or the other as racist or not, racist or conflicted. And you find both.

“There are, for example, letters from when she was 18 on a college visit to Columbia University and she was shocked by seeing an integrated classroom for the first time and those letters don’t hold up well. But then there are letters where she describes the Black dairy farmers who lived on their property in Milledgeville with warmth. There are letters where she even talks about a friend that she makes in grad school at the University of Iowa who is Black and she defends this friendship to her own mother in letters. It’s complicated to look at and I don’t think that we can box her in.”

Like Monk in American Fiction, Gooch used to teach at a university where O’Connor became increasingly problematic because of her use of the N-word. He suspects that she would have relished turning into a provocateur of trigger warnings.

He reflects: “She’s gone into an iffy period because people in the last decade are wondering what to make of her work. Teaching these stories in college, you have to do a version of trigger warnings at least: there’s the N-word in this work and there are obviously racist and bigoted characters.

“Just think, is this the same as the writer? She was documenting like no one else the dialogue and the attitudes and the look and the feeling from the 1950s and early 60s in the south. The world has changed but it’s valuable to see why it changed a lot and where we’ve come from.”

He adds: “In terms of her larger spiritual issues, she’s very relevant. Maybe her stocks rise and fall a little bit depending what decade you’re in but she never seems dated, maybe unfortunately. We are so much living in Flannery O’Connor’s world with violence and dark comedy. There’s a shellshocked quality to reading her work. It doesn’t feel at all dated or sentimental.”

• Wildcat is out now in US cinemas