The pace and incidence of improvements to oceanic travel conditions for American immigrants, during the quarter century preceeding the First World War, were significantly constrained by shipping lines’ capacity considerations. The improvements had no detectable impact on the overall volume of migration, but did influence the flow by route and, probably, the frequency of repeat crossings. Data gathered from transatlantic shipping sources quantify the evolution of travel accommodations for migrants, as “closed berth” cabins, for two to eight passengers each, slowly supplanted older and less comfortable “open-berth” dormitory style quarters. By 1900, roughly 20% of North Atlantic second and steerage (third) class passenger capacity was in closed berths; by 1914, 35%. Steerage alone went from about 10% to 24% closed berths. Accommodation of migrants in closed berths came sooner for northern Europe routes and later for the southern. Prior suggestions attributing the pace of the conversion to competitive impediments, and to discrimination against southern European passengers, are not corroborated. Closed berths for migrants came gradually to all routes regardless of shifting cartel effectiveness, passenger cartels enhanced non-price competition (e.g. in on-board conditions) and differentiation was much more by travel route than by passenger ethnicity. Instead, closed berths were significantly related to the incidence of tourist traffic (highest for north Europe, and seasonally somewhat opposite to migration) because capacity utilization could be raised by using the same quarters for tourists and migrants, provided that the thus interchanged units were closed berth cabins. Growing rates of repeat migration seem to have been mostly a (further contributing) cause, but also partly an effect, of conversion from open to closed berths. Travel condition improvements on North Pacific migration routes lagged the North Atlantic, possibly due to the Pacific’s lower percentage of seasonally offsetting tourism, its less-concentrated migrant flows, and its smaller ships with lower scale economies.
