St. Patrick's Day traditions have origins in both ancient Irish culture and American immigrant experiences. The shamrock symbolized Christianity and national pride in Ireland under English rule. Irish music helped preserve history and culture when the English forbade the Irish language. The legend of St. Patrick banishing snakes from Ireland actually refers to eliminating polytheism. Corned beef and cabbage became a popular St. Patrick's Day meal for Irish immigrants in America, as a cheaper substitute for traditional Irish bacon. Belief in leprechauns stems from Celtic folktales of mischievous fairy-like creatures that guarded gold.