Having spoken with several folks in Cross Plains who actually knew Robert E. Howard, they all say that the portrayal in the film is 99% spot on. The reason being is that it was written from Novalyne Price's book One Who Walked Alone, which is a memoir/journal kept by her about her relationship with Howard. Essentially, you have his girlfriend telling you how things were then. If anybody knew him better, it would possibly be his parents, maybe Truett Vinson or Clyde Tevis Smith, but she was the one that he did his best to open up his heart to. No, she knew exactly who he was and did her best to understand and convey that in her book. It translates to the screen masterfully.
That the film essentially got overlooked by critics, which is a damn shame, it is an amazing film. Love, hate or indifferent about Howard, it is what we know about him from someone who knew him.
Sorry about the semi-thread-jack here, this is a topic I can go on and on about for days.
UncleRhino