What is the form of Margaret Mitchell's novel Gone with the Wind?

Margaret Mitchell's 1936 novel Gone with the Wind conforms to multiple genres. It is a romance novel, with the protagonist, Scarlett O'Hara, manipulating men for her personal benefit while genuinely falling in love with Rhett Butler. It is a historical novel, meticulously depicting the devastation of the American Civil War and the humiliations associated with Reconstruction, if also decidedly biased towards the South of the author's heritage. It is, to a degree, a feminist novel, with its protagonist, Scarlett, a strong-willed, fairly independent woman determined to succeed in business during an era well before women would even enjoy the right to vote. It is a Southern novel, reflecting, once again, the author's Southern heritage and disposition, both for better and for worse. And it can be considered a bildungsroman, tracking its protagonist's development over a period of time, in this case the period immediately preceding the start of the Civil War and continuing into the post-war period. Gone with the Wind is all of this, and its commercial success was a testament to Mitchell's ability to capture the environment depicted in the land of her birth that, unfortunately, fought tenaciously to maintain a horrific system of slavery and racial segregation. 

For many Americans living above the Mason-Dixon Line, their most formative exposure to the South's perspective during and after the Civil War was Mitchell's novel and the film that was adapted from the novel. In fact, the 1939 film adaption, also titled Gone with the Wind, and starring Clark Gable in his most famous role as Rhett Butler and Vivien Leigh as Scarlett O'Hara, was perhaps the first major "blockbuster" among large-budget films. The film successfully captures the atmosphere Mitchell sought to depict during the decade she spent writing her novel. As far as "forms" that describe the novel, as noted above, they include historical, Southern, bildungsroman, feminist, and romance.