American folk music developed from the traditions of European settlers and African slaves who were isolated in rural communities in America. Various genres of folk music emerged including Cajun, bluegrass, polka, spirituals, and blues. Folk music was passed down informally through oral tradition and community performances. Many early folk artists like Frank Blevins and his Tar Heel Rattlers helped preserve traditional folk styles, while modern folk revivalists like Mike Seeger, John Cohen, and Tom Paley sought to document and spread appreciation for folk music traditions.