Common themes in Southern Gothic literature include deeply flawed, disturbing or eccentric characters who may be involved in hoodoo, decayed or derelict settings, grotesque situations, and other sinister events relating to or stemming from poverty, alienation, crime, or violence.
Elements of a Gothic treatment of the South were first apparent during the ante- and post-bellum 19th century in the grotesques of Henry Clay Lewis and in the de-idealized representations of Mark Twain. The genre was consolidated, however, only in the 20th century, when dark romanticism, Southern humor, and the new literary naturalism merged in a new and powerful form of social critique. The thematic material was largely a reflection of the culture existing in the South following the collapse of the Confederacy as a consequence of the Civil War, which left a vacuum in its cultural and religious values. The resulting poverty and lingering bitterness over the issue of slavery in the region during Reconstruction exacerbated the racism, excessive violence, and religious extremism endemic to the region.
The term "Southern Gothic" was originally pejorative and dismissive. Ellen Glasgow used the term in this way when she referred to the writings of Erskine Caldwell and William Faulkner. She included the authors in what she called the "Southern Gothic School" in 1935, stating that their work was filled with "aimless violence" and "fantastic nightmares". It was so negatively viewed at first that Eudora Welty said: "They better not call me that!"
The Southern Gothic style employs macabre, ironic events to examine the values of the American South. Thus unlike its parent genre, it uses the Gothic tools not solely for the sake of suspense, but to explore social issues and reveal the cultural character of the American South – Gothic elements often taking place in a magic realist context rather than a strictly fantastical one.
Warped rural communities replaced the sinister plantations of an earlier age; and in the works of leading figures such as William Faulkner, Carson McCullers and Flannery O'Connor, the representation of the South blossomed into an absurdist critique of modernity as a whole.
Many characteristics in Southern Gothic Literature relate to its parent genre of American gothic and even to European gothic. However, the setting of these works is distinctly Southern. Some of these characteristics include exploring madness, decay and despair, continuing pressures of the past upon the present, particularly with the lost ideals of a dispossessed Southern aristocracy and continued racial hostilities.
Southern Gothic particularly focuses on the South's history of slavery, racism, fear of the outside world, violence, a "fixation with the grotesque, and a tension between realistic and supernatural elements".
Similar to the elements of the Gothic castle, Southern Gothic gives us the decay of the plantation in the post-Civil War South.
Villains who disguise themselves as innocents or victims are often found in Southern Gothic Literature, especially stories by Flannery O'Connor, such as Good Country People and The Life You Save May Be Your Own, giving us a blurred line between victim and villain.
Southern Gothic literature set out to expose the myth of old antebellum South, and its narrative of an idyllic past hidden by social, familial, and racial denials and suppressions.
A resurgence of Southern Gothic themes in contemporary fiction has been identified in the work of figures like Barry Hannah (1942–2010), Joe R. Lansdale (b. 1951),  Helen Ellis (b. 1970) and Cherie Priest (b. 1975).
A number of films and television programs are also described as being part of the Southern Gothic genre. Some prominent examples are:
Southern Gothic (also known as Gothic Americana, or Dark Country) is a genre of acoustic-based alternative rock and Americana music that combines elements of traditional country, folk, blues, and gospel, often with dark lyrical subject matter. The genre shares thematic connections with the Southern Gothic genre of literature, and indeed the parameters of what makes something Gothic Americana appears to have more in common with literary genres than traditional musical ones. Songs often examine poverty, criminal behavior, religious imagery, death, ghosts, family, lost love, alcohol, murder, the devil and betrayal.
The images of Great Depression photographer Walker Evans are frequently seen to evoke the visual depiction of the Southern Gothic; Evans claimed: "I can understand why Southerners are haunted by their own landscape".
Another noted Southern Gothic photographer was surrealist, Clarence John Laughlin, who photographed cemeteries, plantations, and other abandoned places throughout the American South (primarily Louisiana) for nearly 40 years.
William Gibson took an ironic look at the cult of "Southernness" in his novel Virtual Light. Rydell, the stolid, southern antihero, is looking for a job at an LA shop called Nightmare Folk Art—Southern Gothic. The (northern) owner says he finds Rydell unsuitable: "What we offer people here is a certain vision, Mr. Rydell. A certain darkness as well. A Gothic quality....The Mind of the South. A fever dream of sensuality".
Put out by finding himself not southern enough for this New Englander, "'Lady,' Rydell said carefully, 'I think you're crazier than a sack full of assholes.' Her eyebrows shot up. 'There,' she said. 'There what?' 'Color, Mr. Rydell. Fire. The brooding verbal polychromes of an almost unthinkably advanced decay.'"