What makes a movie a "Western".
Some of those mentioned here are westerns because the characters wore a 'cowboy' hat.
Civil War movies aren't westerns.
What is needed is specific minimum elements that must be present in a movie for it to be considered a western.
Below are some suggestions:
Cattle, horses, stagecoach, gunfight, Indians, time period, buffalo, miners, robbers, covered wagon, majestic landscapes, blacksmith, ranch, railroad, campfire, coyote/bear/deer/elk/eagle/buffalo/trout, sodbusters, plains, cavalry and forts.