University of North Carolina athletic teams are known as the Tar Heels because North Carolina is "The Tar Heel State."
One legend has the nickname being applied to the state's residents as long ago as the Revolutionary War. According to this story, the troops of British General Cornwallis were fording what is now known as the Tar River between Rocky Mount and Battleboro when they discovered that tar had been dumped into the stream to impede their crossing. When they finally got across the river they found their feet completely black with tar. Their observation that anyone who waded North Carolina rivers would acquire tar heels led to the nickname first being used.
Others say the nickname was acquired during the War Between the States. During one of that war's fiercest battles a column supporting North Carolina troops was driven from the field. After the battle, the North Carolinians who had successfully fought it out alone, happened to meet the regiment which had fled to safety and were greeted with the question, "Any more tar down in the Old North State, boys?"
"No, not a bit," shot back one of the North Carolina soldiers. "Old Jeff's bought it all up," he went on, referring to Jefferson Davis, President of the Confederacy.
"Is that so? What's he going to do with it?"
"He's going to put it on you'ns heels to make you stick better in the next fight."
Upon hearing of the incident, Robert E. Lee smiled and said to a fellow officer, "God bless the Tar Heel boys."
A letter found in 1991 by State Archivist David Olson lends credence to another more direct theory. A letter from Maj. Joseph Engelhard describes a fight involving men from North Carolina in which Lee was heard to have said, "There they stand as if they have tar on their heels."
The letter, dated August 24, 1864, told the tale of a battle on the outskirts of Petersburg, Va. Engelhard was elected secretary of state for North Carolina in 1876.