Bierce narrates from third person limited point of view in this story, sharing the thoughts and feelings of the doomed Southern planter in a stream consciousness style, while also offering some direct description to achieve the characterization of Peyton Farquhar:
The man who was engaged in being hanged was apparently about thirty-five years of age. He was a civilian, if one might judge from his habit, which was that of a planter. His features were good--a straight nose, firm mouth, broad forehead, from which his long, dark hair was combed straight back, falling behind his ears to the collar of his well fitting frock coat. He wore a moustache and pointed beard, but no whiskers; his eyes were large and dark gray, and had a kindly expression which one would hardly have expected in one whose neck was in the hemp.
Critical analysis of Farquhar's character has varied from the heroic (he died for the Southern cause at the hands of Union soldiers) to the cowardly and foolish (he made a silly mistake playing so easily into the hands of the Federal scout who came to his plantation). If Farquhar is to be believed, he desperately wanted to be a soldier and for whatever reason, was unable to enlist:
Circumstances of an imperious nature, which it is unnecessary to relate here, had prevented him from taking service with that gallant army which had fought the disastrous campaigns ending with the fall of Corinth, and he chafed under the inglorious restraint, longing for the release of his energies, the larger life of the soldier, the opportunity for distinction.
Thus, the interpretation by some of Farquhar as a hero, jumping to help the Confederacy however he could, and paying with his life on Owl Creek Bridge. However, the more cynical readers might interpret the above passage as meaning that Farquhar didn't actually care to enlist, told anyone who listened all the reasons he couldn't, while trying to convince himself that he might still be able to contribute to the cause--jumping immediately at the chance to burn the bridge, with no thought as to the possibility that he was communicating his plans with a northern spy.
Do you have any ideas of why doesn't Ambrose Bierce gives information about the protagonist until the second part?