Inventing America's First Immigration CrisisWhy have Americans expressed concern about immigration at some times but not at others? In pursuit of an answer, this book examines Americas first nativist movement, which responded to the rapid influx of 4. 2 million immigrants between 1840 and 1860 and culminated in the dramatic rise of the National American Party. As previous studies have focused on the coasts, historians have not yet completely explained why westerners joined the ranks of the