Irish immigrants often entered the workforce at the bottom of the occupational ladder and took on the menial and dangerous jobs that were often avoided by other workers. Many Irish women became servants or domestic workers, while many Irish men labored in coal mines and built railroads and canals. Railroad construction was so dangerous that it was said, "[there was] an Irishman buried under every tie."

As Irish immigrants moved inland from eastern cities, they found themselves in heated competition for jobs. The audio recording, Immigrant Laborers in the Early 20th Century, describes how West Virginia coal operators fired union laborers and gave the jobs to Irish, Italian and African-American workers because, “[the] coal company owned them.” This competition heightened class tensions and, at the turn of the century, Irish Americans were often antagonized by organizations such as the American Protective Association (APA) and the Ku Klux Klan.