Residential Segregation By Origin, Nationality and Migratory Origin in Spain: The Case of Barcelona

Residential segregation, understood as the distance in the place of residence between population groups, is usually analysed by calculating different segregation indicators, which inform us of the residential proximity or distance of two populations groups. In these studies, the categorisation used to define the population under study is not a neutral choice, since it affects both the group analysed and what is considered to be the reference population. There are three different types of approaches in the scientific literature. On the one hand, those that use ethnic or ‘racial’ categories, as in the case of the UK and the US, which do not take into account the migration phenomenon. In countries without ethnic categorisation, as in the case of Spain, segregation is calculated either by considering migratory origin and therefore focusing on the country of birth (from which children born in the place of destination disappear), or by analysing nationality (in which some origins disappear from observation in a differential way, especially Latin American origins in the case of Spain). In this paper, we propose to use the latter two perspectives, analysing segregation based on the dissimilarity index by country of birth and nationality between 2002 and 2022, and adding a new calculation that considers the descendants of migrants, based on their identification at census section level with the last census of 2021. This is calculated for the city of Barcelona and some of the cities in its metropolitan region, which should allow us to analyse segregation dynamics in greater depth and to understand the weight of categorisation in the calculation and interpretation of segregation. While the effect of the scale or indicator used has been the subject of intense academic debate, less attention has been paid to the definition of population groups and its effect on the results.