Why was Farquhar hanged in "An Occurrence at Owl Creek Bridge"?

In Section II of "An Occurrence at Owl Creek Bridge," the scout who is posing as a Confederate soldier tells Peyton Farquhar:

"The commandant has issued an order, which is posted everywhere, declaring that any civilian caught interfering with the railroad, its bridges, tunnels, or trains will be summarily hanged. I saw the order."

The Union officers know they are in enemy territory. There were many Southern civilians like Farquhar who were trying to help the Confederate cause by committing sabotage or even bushwhacking Union troops. That is why the order is posted everywhere. The South was a huge place and the Union forces were surrounded by hostile civilians. The commandant posted the order quoted by the scout because he had good reason to fear attacks from self-appointed guerrillas, all of whom owned rifles and hated the invaders.

Peyton Farquhar just happened to be one of the Southern activists who got caught. He was hanged from the bridge mainly to set an example. No doubt his body was left hanging for a long time, so that other Southerners would see it and be frightened. A hanging body sends an eloquent message. 

In Ambrose Bierce's short story, "An Occurrence at Owl Creek Bridge," Peyton Farquhar is a pillar of the American South, which, during the period in question, the Civil War, can be roughly translated to mean a wealthy, upstanding citizen of the Confederacy, and an opponent of the abolitionist movement. Early in his story, Bierce provides the following description of his protagonist who, in the story's opening passages, is about to be executed by hanging:

"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. . .Evidently this was no vulgar assassin."

Bierce goes on to expand upon his description of Peyton Farquhar, noting that this figure "was a well to do planter, of an old and highly respected Alabama family," and that, being "a slave owner and like other slave owners a politician, he was naturally an original secessionist and ardently devoted to the Southern cause." Bierce notes that Farquhar envisioned himself at one point as a soldier in the cause of the Confederacy, but one whose martial interests were impeded for reasons that are extraneous to the narrative.

In section II of his story, Bierce provides background to explain Farquhar's predicament as referenced in the narrative's opening passages, describing the main protagonist's encounter with a grey-clad soldier, presumably a Confederate soldier fighting on the same side of this conflict as that to which Farquhar's sympathies lie. It is soon revealed, however, that this grey-clad soldier is with the Union and has essentially set-up the well-to-do southerner as a presumed saboteur. The "Federal scout" does this by planting in the mind of Farquhar the suggestion of setting fire to the Owl Creek bridge, a key structure important to the movement of Union troops as they advance across the South:

The soldier reflected. "I was there a month ago," he replied. "I observed that the flood of last winter had lodged a great quantity of driftwood against the wooden pier at this end of the bridge. It is now dry and would burn like tinder."

The answer to the question -- why was Peyton Farquhar hanged -- lies in this suggestion cynically offered by the Federal spy. Farquhar takes the bait, so to speak, and attempts to burn the bridge to prevent its exploitation by northern soldiers. 

Peyton Farquhar is a man with a strong feeling of allegiance toward the Confederate cause but, due to his "imperious nature", refuses to go through the proper route of joining the military. It is partly this trait  that makes him a somewhat less likeable character, and for this reason, the reader may feel as if he is deserving of his ultimate fate.

Not knowing anything about military discipline, or about rules of engagement, Farquhar chooses to act as a vigilante by acting on his own accord. He is fooled by a Union soldier into going on their own to burn a bridge that would have blocked the northerners to get through. He got caught as a result, and processed as it is customary: death by hanging.

Perhaps it is the fact that he is a wealthy southerner that has always had things go his way what made him presume that he was above everyone else and should take matters into his own hands. Ultimately, Peyton is not meant to be neither a hero nor a villain, but another consequence of the brutal nature of war.

In Part II of "An Occurrence at Owl Creek Bridge" the Union scout posing as a Confederate soldier tells Peyton Farquhar:

The commandant has issued an order, which is posted everywhere, declaring that any civilian caught interfering with the railroad, its bridges, tunnels, or trains will be summarily hanged.

"Summarily" means without delay, without the customary formalities such as a trial. Peyton is caught red-handed trying to set fire to the Owl Creek Bridge. His capture is not described in the text, but the reader can imagine the scene. One of the reasons the reader can imagine the capture scene so vividly is that Ambrose Bierce has already described it in considerable detail in Part I.

When Farquhar is talking to the Union scout he asks him:

"Suppose a man--a civilian and student of hanging--should elude the picket post and perhaps get the better of the sentinel," said Farquhar, smiling, "what could he accomplish?" 

This shows that he has a strong intention to set fire to the accumulated dry driftwood under the bridge. He might even be thinking about killing the sentinel. Then at the very end of Part II, the reader comes to the ominous lines:

The lady had now brought the water, which the soldier drank. He thanked her ceremoniously, bowed to her husband and rode away. An hour later, after nightfall, he repassed the plantation, going northward in the direction from which he had come. He was a Federal scout.

The reader can visualize Farquhar leaving his horse hitched to a tree and sneaking up to the bridge with a big can of kerosene and some kitchen matches. There are soldiers waiting for him in the dark because their officers have been warned to expect him. Suddenly the scene lights up as the soldiers uncover their dark lanterns. Peyton Farquhar is carrying all the evidence his captors need to convict him of arson. He will be "summarily hanged" the next morning. This is how Part I of the story opens.

A man stood upon a railroad bridge in northern Alabama, looking down into the swift water twenty feet below. The man's hands were behind his back, the wrists bound with a cord. A rope closely encircled his neck. 

When Farquhar walks into the trap, the reader can not only imagine the silent scene with the Union soldiers waiting in the dark and posted in various places near the bridge to forestall any escape, but the reader can even imagine Farquhar's feelings when he realizes he has lost his life, his family, his home, his plantation--everything.

Then Ambrose Bierce, the notorious cynic, plays a sadistic trick on the reader. For a long while it looks as if Farquhar is going to make a miraculous escape. The contrast between most of Part III and the hanging scene in Part I is exhilarating. The reader has been standing in Farquhar's boots waiting to fall to his death, and suddenly it seems as if this is not a story about a man being hanged but about a man escaping that terrible fate. But there is no escape after all. This is realism, not romanticism.

Where did Farquhar die in "An Occurrence at Owl Creek Bridge"?

Peyton Farquhar dies beneath the Owl Creek Bridge.  He was captured and hanged for trying to sabotage and destroy the bridge so that that the Union army could not use it.  

The story is great, and I love teaching it because the ending of it makes my students so mad.  The majority of the story takes place between the moment when Peyton is falling down with the rope around his neck, and the moment that he dies.  It's probably fractions of seconds.  But to Peyton's mind, that is an eternity.  He imagines the rope breaking and himself making a wonderful escape away from his Union captors.  He even makes his way to his home and is hoping to see his wife.  But before his imagination can put him inside of his home . . . the rope snaps taught and kills Peyton beneath the Owl Creek Bridge. 

At the beginning of the story "An Occurrence at Owl Creek Bridge," Peyton Farquhar is standing on a platform at Owl Creek Bridge. He has a rope around his neck and hands tied. The soldiers are about to kill him by dropping him off the bridge so that he dies by hanging from the timbers of the bridge. In the moment just before Farquhar's death, there is a sequence in which time slows down for Farquhar, and he has a long daydream about escaping from the noose and swimming away from the soldiers to return home. The dream sequence ends as Farquhar dies, hanging from the timbers of Owl Creek bridge.

What did Farquhar do to be executed in "An Occurrence at Owl Creek Bridge"?

The situation in Part I is that a gentleman, a civilian, is being hanged from a railroad bridge in Alabama during the Civil War. As the man awaits his execution, he tries to "fix his last thoughts upon his wife and children." He begins to fixate on the ticking of his watch, and he perceives it as slowing down significantly. He considers how he might escape from his situation, ideas "flash[ing]" quickly through his brain. Finally, the sergeant steps off the plank, the other end of which is supporting the man to be hanged (and we can assume that the man's body starts to fall).

In Part II, we learn the man's identity and get some background information on him (including what he must have done to deserve hanging). He is Peyton Farquhar, a slave owner and vehement supporter of the Southern cause:

No service was too humble for him to perform in the aid of the South, no adventure too perilous for him to undertake if consistent with the character of a civilian who was at heart a soldier, and who in good faith and without too much qualification assented to at least a part of the frankly villainous dictum that all is fair in love and war.

We learn that, not long before, a man dressed as a Confederate soldier (who was really a Federal scout) visited the Farquhar plantation and told Farquhar that "a great quantity of driftwood" had built up against the bridge and "would burn like tinder" now that it was dry. This would destroy the railroad bridge, obviously, and a Union commandant, the soldier said, had "issued an order . . . declaring that any civilian caught interfering with the railroad . . . will be summarily hanged." This is a big clue that the railroad is essential to the Yankee war effort. Farquhar, a loyal Southerner, evidently decided to burn down the bridge in order to thwart the Union army and is now being hanged for it.

Part III tells us what goes on in Farquhar's mind as he falls from the bridge with the noose around his neck. We know that his brain seems to be running quickly because of the rapidity of his thought at the end of Part I as well as his perception of the slowing down of his watch. The entirety of Part III occurs in the hanged man's head—except for the final lines. The rope pulls taut, his neck is broken, and his body swings lifelessly.

Peyton Farquhar is a wealthy plantation owner who attempts to help the Confederacy by burning down the Owl Creek Bridge, which is central to the Union's efforts to invade the South. In part two, a Union spy arrives at Peyton Farquhar's estate and informs him that the Union commandant has issued an order that any civilian caught interfering with the railroad, its bridges, tunnels, or trains will be hanged. The Union spy is able to manipulate Peyton into believing that he will be able to overtake the single sentinel posted by the bridge and burn it down, which would halt the Union's advance. Unfortunately for Peyton, he is captured by the Union troops and sentenced to hang from the Owl Creek Bridge. As Peyton is waiting to be hanged, he daydreams about escaping and traveling home to see his family.

Farquhar was a Southern planter with obvious interest to protect in the South, so naturally he supported the Confederacy. When a Confederate soldier stops by his plantation one day, Farquhar helps him develop a plot to burn down the Owl Creek Bridge. He informs the soldier how easy it would be to burn because of a large amount of drift wood piled underneath it.

Later, we learn that the Confederate soldier was actually a Federal scout. Farquhar’s plot to burn the bridge to prevent the infiltration of the Union is his crime and the reason for his execution.

The situation in this story is that the Union army has invaded deep into the South.  They have gotten near to Farquhar's plantation.  He does not like this and he wants to do something to fight back against them.

What Farquhar does is to try to sabotage the bridge that crosses Owl Creek.  According to the laws of war, it is illegal to try to commit sabotage unless you are in the uniform of your country's armed forces.  Otherwise, you are a spy and you are liable to be executed.

Of course, the guy who egged Farquhar into doing it was committing an illegal act since he wasn't in uniform, but he didn't get caught.

How is Farquhar depicted at his hanging in "An Occurrence at Owl Creek Bridge"?

In "An Occurrence at Owl Creek Bridge," Farquhar is depicted, at the time of his hanging, as anxious and terrified by the prospect of his execution and perhaps also regretful for his own earlier decision to attempt to destroy the bridge.

This sense of anxiety is already, at the very least, implied in the story's first chapter, as Bierce describes Farquhar's own train of thought in the moments before his death, with his attention drawn towards "his unsteadfast footing" and "the swirling water of the stream racing madly beneath his feet" (ominous imagery on Bierce's part). While trying to dedicate his last thoughts to his family, he is driven to various distractions and tormented by the sound of his own ticking watch. The combined effect of these details suggests the impression of someone ill at ease.

At the same time, there are also the details contained in his imagined escape. Note, first of all, just how terrifying this vision actually is, as Farquhar must first escape the noose strangling him (even while being submerged underwater for that matter), before next overcoming potential death by firing squad. This entire scene is shaped by a sense of desperation as he must struggle against overwhelming odds.

Finally, there is the very end of his vision, where he sees himself reunited with his wife. Here particularly, there seems to be a possibility of very real regret on his part: after all, he was the one that left home in order to destroy the bridge in the first place, driven by his enthusiasm for the secessionist cause and military life. In that sense, it is noteworthy that, at the very end, his mind is now focused on the life he left behind.