Final answer:
During the economic expansion post-Civil War, immigrants played a crucial role in the labor force, often working for lower wages than native workers, which contributed to economic competition and the rise of nativism.
Step-by-step explanation:
The immigrant experience in the United States during the 19-th and early 20-th centuries was marked by challenges and opportunities. After financing their journey, many immigrants found themselves in a precarious financial state, similar to that of sharecroppers, earning barely enough to survive. Yet, as the US economy expanded rapidly post-Civil War, some were able to escape the cycle of debt. The labor of immigrants was a coveted commodity, as they were often willing to work for lower wages and longer hours. Native-born workers, particularly men, found themselves competing with German and Irish immigrants in trades like furniture making or manual labor like railroad construction and canal digging. This economic competition, fueled by a burgeoning industrial output, was a significant contributor to the rise of nativism and the defensive posture of certain American social groups against cultural diversity.