The agony and desperation of slavery, the sheer magnitude of the total dehumanization that defines it, has been captured in “The Birth of a Nation” by director, star and writer Nate Parker with stunning force.

Movies have covered this terrain extensively but rarely with the sort of vision that permeates every frame of this masterwork, in which Nat Turner (Parker) becomes increasingly seized with the conviction that the only possible recourse for him and his fellow humans held in bondage in Southampton County, Virginia, circa 1831, is to rebel against their captors.

For much of the story, Turner is but a preacher exploited by his cash-strapped owner (Armie Hammer), who earns money bringing Nat to nearby plantations to offer a message of the gospel slanted toward obedience and respect.

Parker presents Turner’s shift toward a violent uprising as a religious awakening. There’s a higher presence palpably felt here and the movie might be seen as Turner’s extended conversation with god. The picture is filled with scenes of silent, determined prayer — against the weeping willows that define this deep rural country, the barn-turned-church decorated with a simple, large cross, and even at unexpected moments where Turner is suddenly and irrevocably filled with his memories of the horrific things he has seen and experienced. This is a radical and uncompromising way of viewing these events; Parker prefers anger and vengeance to sentimentality, and his movie is infused with righteous fury.

Of course, Parker’s dark personal history has threatened to overshadow the picture — the events surrounding his 2001 rape trial, where he was acquitted, have been widely covered in recent weeks, complete with the revelation that his accuser committed suicide in 2012.

There’s no easy answer to the age-old question of what to do when events such as these become entwined with a work of undeniable artistic genius. Some will boycott the movie, others will separate things, but whatever the case, the critic must endeavor to seriously and objectively treat the work at hand, and there’s no question Parker has made one of the year’s greatest films.