This chapter situates the late-in-life mobility of hostel residents in its geographical, historical, and theoretical contexts. As noted in Chap. 1, the vast majority of hostel residents hail from France's former colonies in North and West Africa. Section 2.1 charts the geography and history of migration from these areas. Section 2.2 pursues the historical theme by elaborating how France's migrant worker hostel accommodation came into being in the late 1950s and subsequently developed. While originally envisaged for a young working-age population, the migrant hostels now host an ageing cohort of men who, defying expectation, do not return definitively to their families at retirement. Section 2.3 sketches four distinct theoretical frameworks which have the potential to explain this counter-intuitive behaviour: these are the new economics of labour migration, structuralism, transnationalism, and social systems theory. I conclude the chapter with a discussion of the methodological implications which follow from the study's stated aim to explain hostel residents' late-in-life mobility.