Ambrose Bierce had an interesting history. He grew up in Ohio, and he worked for an abolitionist newspaper. Later, while living in Indiana, he enlisted, and his unit was sent to Virginia to “wrest the pro-Union western Virginia counties away from the rest of Confederate Virginia" (HistoryNet). For the remainder of the war, Bierce would see and experience some of the terrible realities that would shake his idealism, and in the end, leave him wounded and bitter.
It is safe to say, then, that if Bierce was biased against anything, he is biased against war. In “Occurrence at Owl Creek Bridge,” the first scene depicts Farquhar, on the bridge, about to hang. We don’t know what side he is on, at first, but we are given a few hints that suggest he is probably a Confederate sympathizer. Later in the story, we learn that he is a plantation owner who has been trying to blow up the bridge. His information about the bridge came from a Union spy, dressed as a Confederate soldier.
While Bierce does seem to be putting down the Confederates in this part of the story, he also puts the Union down by showing their ridiculous tactics for “catching” him. For example, everyone shoots at him and no one hits him. Also, they stand on the riverbank when they could go into the water and catch him. If either side comes out worse, it is the Confederate side because they are fooled by the man dressed up in the Confederate soldier’s uniform.