Providing a Nordic historical perspective, this collection aims to further our understanding of trade union activism and its role in modern society. Contributions from a range of leading scholars analyse the organisational conditions of mobilisation that were deployed by Nordic unionists, and explore the way that they interacted with other forms of social and political protest during the twentieth century. Covering illegal or so-called wildcat strikes, blockades, demonstrations and other activist measures, the authors examine the way that trade union activism in the Nordic countries aimed to move the political combat zone from the meeting rooms of the respective confederations into the streets and the public domain. The collection focuses on cases from Denmark, Sweden, Norway and Finland, but comparisons are also made with countries such as Iceland, Germany, and the USA. Exploring the ways in which political parties have intervened in Nordic trade union activism since the early twentieth century, this unique collection offers new insights for those interested in labour market dynamics and the complex process behind the formation of salary and employment conditions.