Light in August was published in 1932, just twenty years before Harper Lee began writing. In comparison to her books, it's a heavyweight work of literature, initially striking me for its wordplay linguistic inventiveness and its piledup evocative paragraphs. It also struck me for its sexual frankness. It's a slow read because Faulkner is in no hurry and does not maintain a single (or even a dual) narrative line. I found this unsatisfactory only at the end when the introduction of a completely new character, the State Captain Grimm - Joe Christmas's eventual killer - delays the work which is then delayed again by the historical musings of Hightower.
On those Lists which are everywhere, it ranks in the Top 100 American novels of the 20th century and no doubt even higher among novels which treat of the American South and the legacy of the Civil War, whites and negroes, Confederates and Yankee abolitionists. But its themes are in many respects more personal than sociological, focussing on a set of lives early damaged and badly so and intersecting in ways which bring out that damagedness. There is only the merest hint of the possibility of redemption, in the short final chapter.
It's 380 pages in my edition; I doubt I will read it again, even though it is the kind of richly-textured book which would repay a second reading.