Randall Flagg in The Stand is one of Stephen King's most important villains with a complex backstory, including a dark connection in the book that is left out of both the 1994 miniseries and the latest adaptation for CBS All Access. While this connection was clearly established in Stephen King's novel, the inclusion of this detail would have likely been too much for television audiences to stomach.
Randall Flagg is first introduced in King's novel on page 171 of the Complete and Uncut version. He's walking south on US Highway 51 in Idaho heading for Nevada. He is described as a "tall man of no age in faded, pegged jeans and a denim jacket." Interestingly, he doesn't have much of a memory. He can't where he comes from other than he "originally came from Nebraska" and most of his memories are of being a part of various extremist groups. He shows up and encourages people to take the path that leads to the most chaos and pain.
One of the extremist groups Flagg re being a part of is the KKK. He also mentions reading Mein Kampf just for the fun of it. He's been a part of rapes, lynching, castrations, and the burning of Black communities. However, to further complicate things, he has also been a part of Black hate groups as well. In New York, he was once known as Robert Franq, and "his claims that he was a black man had never disputed, although his skin was very light." There, he took part in the killing of six cops in New York and New Jersey. Randall Flagg is a man of equal-opportunity hate, but his involvement with racial hate groups, particularly the KKK, was likely too heavy and controversial for television. This is the most likely reason behind why both existing miniseries adaptations have opted to leave certain aspects of Flagg's history out.
When Stephen King wrote this background for Randall Flagg in The Stand, he did so in a clear attempt to portray him as evil. What's more evil than an extremist hate group like the KKK? Worse still is the fact that he's an equal-opportunity hater. Personally, Flagg doesn't hate anyone, and his primary goal is to manipulate humanity to do horrible things. Given that, it makes sense that Flagg would align himself with any group that would sow threads of hatred or disparity throughout the world.
That said, The Stand is a story rooted in certain fantastical elements, such as the shared dreams the God or Gan) that seems to know what events have to transpire in order for Flagg's plans to fail. In a story with these elements, bringing the real-life horror of a group like the KKK into it is a bit too much, and would have likely distracted audiences from the overall story and Flagg's greater purpose. Adding this detail in might have given audiences a sense that Flagg is racist when he's actually not. In The Stand, Randall Flagg is an equal-opportunity sickness that preys on humanity's prejudices and fears. King describes him as a malignant cell waiting to begin raising a tumor as if Flagg is a cancer of the human race. A more simplistic classification (such as Flagg being racist) would have missed the point.
