Sam was reportedly ordered by General Robert E. Lee to guard the borders between the Confederate States and the United States during the American Civil War (1861 - 1865). He is oblivious to the fact that the war ended "almost ninety years ago" ("I ain't no clock watcher!") and continues to await new orders that will never come from the now long-deceased General Lee, refusing to allow any Yankee to cross the line.
Bugs fights to cross the line. He disguises himself as a slave, Abraham Lincoln, "General Brickwall Jackson", and Scarlett O'Hara to little effect. He at last succeeds in removing Sam from his guarding post when he disguises himself as an injured Confederate soldier and informing him that "the Yankees are in Chattanooga" in Tennessee. Sam marches to "Chattanoogee", and uses a rifle to threaten the New York Yankees, preventing them from competing in an exhibition baseball game against the Chattanooga Lookouts.
- The Cartoon Network version of this cartoon cuts out Sam yelling "CHARGE!" after Bugs first tries to cross the Mason-Dixon Line due to the short scene featuring the Confederate "bars and stripes" flag (which is considered a very controversial flag in American culture/history). Cartoon Network also cuts out the entire part where Bugs poses as a slave, then gets his cover blown when he sings "Yankee Doodle," shoves a whip into Sam's hands, begging Sam not to beat him, and Bugs posing as Abraham Lincoln to chastise Sam about whipping slaves. Instead, it goes from Sam yelling, "So, scram Yankee!" to Bugs diving into a tree hole. These edits were also seen on the version shown on the former Kids' WB as well as on Cartoon Network's sister channel Boomerang.
- Unlike the versions shown on The WB, Cartoon Network, and Boomerang, the sequence where Bugs poses as a runaway slave going back to the South, then blowing his cover by singing "Yankee Doodle" was mostly left in on the FOX and syndicated version of The Merrie Melodies Show. The Merrie Melodies Show version only cut Bugs putting a whip in Yosemite Sam's hand, pleading for Sam not to beat him, and Bugs posing as Abraham Lincoln and chastising him for whipping slaves before Bugs' cover is blown again and Bugs dives into a tree (the edited version goes from Bugs getting caught singing "Yankee Doodle" to Bugs diving into the tree, with some of the whip part left in by mistake). It should be noted that, despite cutting the slave part, Sam's introduction scene (which features the controversial Confederate "bars and stripes" flag) was not cut on either version of The Merrie Melodies Show. It should also be noted that a similar scene on "Wise Quackers" of a character (Bugs in "Southern Fried Rabbit"; Daffy in "Wise Quackers") making another character (Yosemite Sam in "Southern Fried Rabbit"; Elmer Fudd in "Wise Quackers") out to be a slave driver (with the former character dressing up as Abraham Lincoln and chastising the latter character for it) wasn't edited. 
- In addition, The Merrie Melodies Show (both versions) edited Sam being blasted by a cannon by replacing the scene with a still of Bugs (dressed as a Southern Belle) blocking a door (which was recycled from the next scene).
- Most of the scenes from this cartoon were used in the TV special Bugs Bunny: All American Hero.
- Despite the censored scene being cut from TV airings, a scene where Bugs pretends to be Abraham Lincoln and Sam finding out he's been tricked is shown in the beginning of the ToonHeads episode "Southern Fried Cartoons" before this short plays.
- This is the final Looney Tune short to be given a Blue Ribbon Reissue. It was reissued in 1969, the year that the Warner Bros. theatrical shorts ended their run.