Goofs

Grandpa Wagoneer says that he was 18 years old at the 1893 land run. This would make him 60 years old in 1935. John McIntire looks much older and was, in fact 75, when the movie was made. However, people's appearances often are not a reflection of their chronological age. Also, actors often play roles where their characters are of a much different age than they are.

The highway patrolman pulls Red over and tells him it's illegal to drive with only one headlight, yet he pulled him over in the daytime, so the car's lights weren't even on.

Ryman Auditorium is used as the setting for the Opry. This venue was not used until the 1940s, and the movie takes place in the 1930s.

(at around 1h 51 mins) Uncle Red takes a slug of Southern Comfort in his bed. There is a bar code visible on the label of the bottle.

There are several shots of the surface of the road the characters were driving on which showed a white edge line to delineate the border between the lane and the shoulder of the road. Roads in the US did not have those stripes in the '30s.

The guitar Red Stovall is playing is a Gibson L-5C manufactured around the 1970s. Although Gibson launched the L-5 in 1922, the particular instrument Red plays in the movie is definitely not from the era the movie was set in. The L-5P was launched in 1939 and was superseded by the L-5C in 1948. The letter "C" in L-5C stands for "cutaway" whereas the letter "P" in L-5P stands for "premiere". The tuners and the "Gibson" logo on the guitar's headstock are distinctly 1970s.

Supposedly taking place in Oklahoma, very high mountains in the background which do not exist in Oklahoma.