Harry McCarthy was an Ulster born variety entertainer and comedian in America in the mid 19th century. In 1861 he wrote the song "The Bonnie Blue Flag," about the unofficial first Confederate flag, using the tune from "The Irish Jaunting Car." The song was extremely popular, rivaling "Dixie" as a Confederate anthem. The song lost some of its popularity when, late in the war, McCarthy left the South for Philadelphia, Pennsylvania.