http://members.aol.com/h4texas/rose.htm"The Yellow Rose was first issued as sheet music in 1858, and the New York City publishers identified its author only as "J. K." The actual identity of this composer has never been established. It was reissued during the war by a music publishing house in Macon, Georgia, Confederate States of America. Popular not only during the war, it has remained a widely-loved classic to this day.
The origins of the song are as mysterious as its unnamed author. Attempts by Texas folklorists to claim that the song was in oral circulation during the time of the Texas republic are patriotic but completely unpersuasive.
It seems somewhat likely that the song was inspired by an alleged incident of the Battle of San Jacinto. According to some sources, the Mexican General Santa Anna was detained at the start of the battle by his entanglement with a mulatto women named Emily, a Texan lass who was traveling with the General in a questionable capacity. Some suggest that she is the Yellow Rose celebrated in the ballad."