Corrected entry: Jeremiah finds Hatchet Jack frozen to a tree and begins to approach him. In every close-up shot of Hatchet Jack, you can see Jeremiah's rifle resting on the tree behind him. The rifle is then absent during shots from further away as Jeremiah approaches. Jeremiah does not place his rifle there until he reaches Hatchet Jack and begins reading his note. (00:10:55)
Corrected entry: Near the end of the movie, Johnson states that he is heading to Canada, however Canada wasn't a country until the 1860's while the movie is only based around 1840.
Correction: Canada was known as Canada long before it became an official country. It was called Kanata by aboriginals for centuries before it became a British colony called the Province of Canada in 1841. The name was taken from the Iroqouis around 1535 by European explorers.
Corrected entry: In the scene where Jeremiah attacks the Indian camp, he jumps off his horse with a Hawken muzzle loading rifle in each hand and shoots each as he is running toward the Indians. A Hawken rifle is very heavy and kicks like hell making it virtually impossible to pull off such a feat.
Correction: "Virtually" impossible means it is possible, however unlikely, invalidating this entry.
Correction: I just watched this over and over to confirm. The rifle does not appear leaning on the tree until after Jeremiah is standing in front of Hatchet Jack. The scene cuts away for a moment (if you want, leaving him time to lean his rifle against the tree) when the scene opens up again he is pulling the will from his frozen shirt.