How is the Appomattox Court House of importance in To Kill a Mockingbird?

The Civil War is mentioned several times by Scout in
To Kill a Mockingbird, and remembrances of the war are still very
much alive in the town. Scout's much older cousin, Ike Finch, is the last surviving
veteran of the war still residing in Maycomb, and many Confederate heroes' names find
their way into the text: Robert E. Lee, "Stonewall" Jackson, Joe Wheeler and John Bell
Hood among them. The reference to Appomattox Court House, Virginia, the site of Lee's
surrender in 1865, comes from Mr. Avery on the night of the early cold spell that hits
Maycomb. Mr. Avery comments that it "Hasn't snowed in Maycomb since Appomattox," and
blames the bad weather on bad children like Jem and Scout. He was incorrect on both
counts, since according to Eula May, it actually hadn't snowed since
1885.