Considering the history of workers' and socialist movements in Europe, Frontier Socialism focuses on unconventional forms of anti-capitalist thought, particularly by examining several militant-intellectuals whose legacy is of particular interest for those aiming for a radical critique of capitalism. Following on the work of Michael Löwy, Quirico & Ragona identify relationships of “elective affinity” between figures who might appear different and dissimilar, at least at first glance: the German Anarchist Gustav Landauer, the Bolshevik Alexandra Kollontai, the German communist...