The term "Scottish-Irish" refers to the descendants of Scottish Presbyterians who settled in Ireland during the 17th century, particularly in the province of Ulster. These settlers, often called "Ulster Scots," brought their culture, language, and traditions to Ireland, where they lived alongside the native Irish population. In the 18th century, many Scottish-Irish emigrated to North America, particularly to the Appalachian region. They played a significant role in shaping American culture, especially in areas like music, folklore, and frontier life. Today, the Scottish-Irish heritage is celebrated in various festivals and cultural events across the United States.