When in 1996 historian Kenneth Greenberg published a collection of documents related to the short-lived 1831 slave uprising led by Nat Turner in Virginia, he closed his introduction by writing, “We are ready for a new retelling of the Nat Turner story.” That’s what Nate Parker provides in “The Birth of a Nation”—a title that’s obviously intended as a rebuke of D.W. Griffith’s 1915 film of the same name, which remains a cinematic classic despite its racist overtones and its portrayal of the KKK as heroic. But Parker’s film is also clearly a rejoinder to William Styron’s Pulitzer Prize-winning 1967 novel, which provocatively depicted Turner in decidedly negative terms. By contrast he’s here clearly treated as a hero in the mode of a Spartacus or a William Wallace.

That alone would engender controversy among historians, who are quite divided in their assessments of Turner. They will undoubtedly also point out how speculative much of the screenplay is—necessarily, because the sources on the rebellion are scanty and the few details they provide are sometimes contradictory. Even the topographic details will be subject to criticism—the Georgia landscape where the film was shot, for example, is hardly the same as Virginia’s. And agriculturally, the region was not the site of the large cotton plantations that seem to dominate in the film, but a place of small, struggling farms with varied crops and livestock.

But those historiographic criticisms won’t be the most powerful ones troubling the film. Since its successful festival screenings, serious questions have been raised about an accusation of rape that was lodged against Parker (and his friend and co-writer Jean McGianni Celestin) while they were student athletes at Penn State. Though he was acquitted at trial, the matter has dogged Parker, and some have argued that the picture should be boycotted as a result.

While there can be no doubt about the seriousness of that charge—and the fact that the alleged victim committed suicide in the intervening years adds to it—the controversy stands apart from the question of the film’s quality. “The Birth of a Nation” deserves to be assessed on its merits as a movie, not as a historical documentary or proof of its maker’s moral character, and in that respect it’s a strong piece of work—a tale of resistance to oppression that bears comparison with the similarly-themed films of Stanley Kubrick and Mel Gibson (another director with personal issues) mentioned above. It would be a stretch, however, to describe it as akin to history written with lightning–which is what Woodrow Wilson famously said of Griffith’s film a century ago.

Parker starts with African traditions that prevailed among slaves, signs that prophesied a leadership role for Turner as a child (played by Tony Espinosa). He then recounts, in a section charged with dramatic license, the flight of Turner’s father and the boy’s early years, marked by portents and what amounts to good luck—an ability to read without being taught, which earns him instruction at the hands of the pious mistress of the farm, Mrs. Turner (Penelope Ann Miller), and a boyish friendship with her son Samuel (Griffin Freeman). That relatively easygoing master-slave relationship continues into adulthood between Nate (Parker) and Turner (Armie Hammer). The latter even accepts a suggestion to purchase Cherry (Aja Naomi King) as a wife for Nate.

Nate also becomes a means of extra income for Samuel when nearby farmers prove willing to pay for him to come and preach to their slaves, as he does to Turner’s, using his knowledge of Scripture to encourage them to obey their masters. Ironically, however, coming in contact with blacks who are so brutally mistreated causes him to rethink the Biblical message in a far more aggressive fashion; and when he is whipped for baptizing a white man and Cherry is attacked, all those events—along with visions that urge him to a higher calling—lead him to turn to violence against the oppressors.

The uprising itself is depicted unsparingly but without wallowing in gore, although Parker undoubtedly takes liberties in constructing a rather large final confrontation that never happened (as well as a villain, vicious slave-catcher Raymond Cobb, played by sneering Jackie Earle Haley) to end his retelling on a cinematically satisfying note. He also embellishes on a passing suggestion in the sources that Turner might have been betrayed from within his band, turning it into a certainty and highlighting it.

But these are tropes that are common to a story with this template—a righteous battle against cruel oppression—and merely show that Parker understands the model he’s using and fills in the missing pieces with informed imagination. (The details of Turner’s relationship with Cherry are totally unknown, for instance, but Parker fashions an account no less touching than the one Dalton Trumbo did for Spartacus and Lavinia). The result, as scholars will argue, is often historically dubious, but as cinema it’s quite effective. Parker is solid as Turner, conveying the man’s sense of mission, and as director he secures remarkably convincing performances down the line, even by those in the smallest roles (though he certainly doesn’t keep Haley on a short leash). That’s true of King as Cherry, but it’s especially so in the case of Hammer, who’s often been wooden but here is looser and more credible.

In terms of the production, the film is surprisingly polished for a modestly-budgeted one, with the overall design (by Geoffrey Kirkland), sets (Jim Ferrell) and costumes (Francine Jamison-Tanchuck) creating a genuine sense of time and place that’s well caught in Elliot Davis’ widescreen camerawork. It’s only in the sequences of Turner’s ecstatic religious visions that the picture stumbles visually, opting for gauzy images that lack a true sense of wonder, though elsewhere Steven Rosenblum’s editing overemphasizes stateliness to the detriment of narrative energy. Henry Jackman’s score, on the other hand, is genuinely imaginative.

While “The Birth of a Nation” is not without flaws, it is overall a strong, committed piece of work. Also a provocative one: a teacher might do well to couple it with a reading of Styron’s book and then watch the fireworks fly—after first assigning Greenberg’s book for context, of course.