Appalachian English is a dialect of the English language. It is spoken in the Appalachian Mountains region. Research suggests it is one of the most unique dialects in the United States.

Since the 1930s, a lot of research has been done to figure out where the dialect came from. One theory is that the dialect is a remnant of Elizabethan (or Shakespearean) English that had been preserved by the region's isolation. Another theory suggests that the dialect developed out of the Scots-Irish and Anglo-Scottish border dialects brought to the region by some of its earliest British Isles settlers, who were from the border of Scotland and England.