In a 2018 interview, Guy Pearce said that this is his favorite of all of the movies he's ever done.
All the firearms are period replicas. Famed gunsmith Buck Merry crafted each one with his own two hands. They were indeed transported to set via steam locomotive.
The wardrobe was handmade to be as authentic as possible, and even the buttons were all handmade for this movie.
The photograph used to represent the Hopkins family is actually of photograph of a Missouri sharecropper family named Parson. They were all murdered in 1906 by Jodie Hamilton following a dispute over a stolen saddle.