The contributions in this book emphasize three types of historical situations. First, situations where racially structured unfree labour relations (e.g., slavery) turned into free labour markets, or where previously unfree labourers tried to enter the labour market as immigrants. Second, situations where white settlers subjugated peripheral societies, thereby creating a new labour market. The main issue in these situations is whether and, if so, how these situations resulted in racial segmentation. Third, situations where a long established labour market, segmented along class lines but not along racial lines, is confronted with immigrants. The 23 contributions deal with countries on all continents in the period after 1830.