This working paper (open access) investigates how the tenor of the political climate during a person’s youth affects his or her attitudes towards immigration in adulthood. We analyze why cohorts formulate distinct patterns in attitudes towards immigration through a collective process of political socialization during the formative years. The theoretical arguments are tested using hierarchical age-period-cohort modelling across twelve cohorts in nine European countries using micro attitudinal data (2002 – 2016) integrated with historical macro political data. We find that contextual exposure to principles of equality and tradition in the formative political climate are central to the formulation of a person’s attitudes towards immigration later in life. While the prevalence of the principle of equality affects immigration attitudes in adulthood positively, the principle of tradition does so negatively. The findings imply that even subtle and cyclical shifts in national politics affect the political orientations of those undergoing the process of political socialization.