The term "Scots-Irish" refers to the descendants of Scottish Presbyterians who settled in Ireland during the 17th century, particularly in the province of Ulster. These settlers faced economic and religious challenges, leading many to migrate to North America in the 18th century, where they played a significant role in the early development of the United States. Scots-Irish immigrants often settled in the Appalachian region, bringing their distinct culture, traditions, and a strong sense of community. They contributed to the formation of American identity, particularly in areas like Kentucky and Tennessee, and are known for their influence on American folk music and frontier life.