What is the name of this movie?

It's a movie with John Wayne in it. Takes place as the Civil War ends. Wayne is a Union General or something and he gets lost and ends up alone with confederates. A later scene is where this confederate guy is looking at a newspaper or somethin in his tent when it's raining and curses when he finds out the war is over. another scene is where theres a former confederate ( half mexican half native american) who heres gunshot at a bar and comes down in his underwear. theres also a lady in it who wants reveng against these 2 men i think and john wayne and the half mexacanhalfindian help her find them. they also face off against outlaws. Really need to know what the title is please. Thanks