Found in a 1904 newspaper, several Confederate Generals names were used in advertising a tonic called "Peruna", known for it's 18% alcohol content. It also became the subject of the SMU
fight song and mascot. ""medicine," which just happened to be about 18% alcohol, was "famous for its kick." Being 1932, SMU students enjoyed singing (to the tune of "She'll be Comin' Round the Mountain") "She'll be loaded with Peruna when she comes..." Thus, what better name for their new mascot than Peruna! Since then, each pony to serve as the university's mascot has taken the name Peruna as a representation of the fighting spirit that SMU has."
Link to the add with the Generals endorsement.