"As background for the work of the Panel on Demographic and Economic Impacts of Immigration, we present a broad overview of the scholarly literature on the impacts of immigration on American life in the late nineteenth and early twentieth centuries. We emphasize at the outset that this is a formidable undertaking. There is an enormous literature on the subject ranging over every conceivable genre. These include nineteenth-century political broadsides, serious and masterfully written histories, the 42 volume report of the first Immigration Commission appointed in 1907, focused cliometric studies appearing in scholarly journals, autobiographies that witness the era of high immigration, two forthcoming economic histories of pre-World War I immigration (Ferrie, 1997; Hatton and Williamson, 1998), obscure statistical compendia, and theoretical analyses some of which are highly abstract and mathematically intricate. The subject is also emotional and controversial. In the past, as today, immigration policy arouses strong feelings and in some cases these have colored the analysis offered. As Kuznets and Rubin suggested, dispassionate inquiry is hard to find. Many authors express their conclusions with a degree of certitude that is difficult to justify from the evidence they offer. Writers on opposite sides often have failed to take account of the evidence and arguments of their opponents. On many aspects of the question a modern consensus of scholarly opinion cannot be found."