Where in the story do references to the Civil War occur? How does that war play a role in the story?

Just a quick note:  "A Rose for Emily" is obviously
fiction.  When it was published has nothing to do with when Emily was born.  You can't
equate the story's publication date with Emily's death.  And how long Faulkner was
working on the story is irrelevant.  I can write a story about someone born in 1508, or
1203, or 2098.  The date I publish the story has nothing to do with my character's age. 
There is no reason to assume that Faulkner wrote the story immediately after Emily dies,
unless there is some external evidence that I don't know about.  You can figure out her
chronology from the story if you want, but you can't figure it out by assuming the
publication date has any chronological relation whatsoever with Emily's
death. 

The Civil War mentions are important to the story
because Faulkner is writing about the reconstruction stage of the American South
following the war.  Notice that everyone is poor.  The war devastated the South.  It not
only destroyed the South's economy, but most of the battles, etc., took place in the
South.  The region was ravished by the war.