This article undertakes a journey through the historiography of the working class in three of the countries in Western Europe where the movement was strongest and most successful: France, Italy and Spain. The aim is to show commonalities and differences through the comparative study of these three cases. Clearly, political circumstances – international and civil conflicts; dictatorships and democratic transitions – affected the process in different ways in each of these historiographies, but, in the end, the road taken – despite the very distinct rhythms and intensity – was largely the same. Initially centred on a “militant” historiography – basically revolving around a study of the working-class movement – and moving towards (and not without complications) a university-based one with pretentions of a scientific nature, this was a transition that signalled fundamental changes in the way of understanding the writing of the history of the workers.