Before 1890, Wales was the world's leading producer of tinplate, and the United States was its primary customer. With passage of the McKinley tariff on tinplate that year, however, the industry entered a vigorous expansion in the US but went into a steep decline in Wales. Underemployed tinplate workers in Wales migrated to the US, where their skills were now in high demand, and in the process created extensive occupational networks and a transnational niche community. Grounded in the nineteenth-century ideological ideals of female domesticity, the male breadwinner, and the family wage, Welsh tinplate men hoped to achieve these middle-class gender aspirations by completely removing women from the mills in America. That goal was challenged in...