Why another book on German Social Democracy, given the extensive existing scholarship on the topic? Andrew Bonnell poses this question at the outset of his book and gives several significant answers, from the topic's relative neglect in recent decades, due to a general shift from social history to cultural history, to the fact that the prewar SPD deserves reevaluation to acknowledge its successes and to move beyond fixation on its failures in August 1914. The latter is Bonnell's main aim in the book, as he highlights the SPD's skill in attracting a mass working-class base, its responsiveness to German workers’ everyday experiences, and its ability to mount a growing electoral challenge to traditional power structures (albeit cut short by war in 1914). August 1914 figures as a miscalculation born of the moment, based on inadequate information amid fast-moving events, rather than proof of the party's fatal flaws.

In Chapter 1, Bonnell addresses the cult of personality around Ferdinand Lassalle. Charismatic and autocratic in his control over the party, Lassalle was celebrated by many party members both in life and long after death. Lassalle festivals enjoyed fervent enthusiasm that worried left-wing leaders, including Friedrich Engels and August Bebel, as a sign that the working masses were easily seduced by semi-authoritarian charisma. Bonnell argues instead that the cult's three phases have to be understood in separate terms. In the 1860s, workers were still politically unschooled and thus more easily drawn to the cult's quasi-religious charisma, especially those coming from a Catholic background. During the era of the Anti-Socialist Laws, the cult shed its religious connotations and became a clandestine form of proletarian resistance against state repression. After 1891, party leaders actively used the cult and its festivals to counter the state's intensified nationalist traditions like Sedan Day, with Lassalle as a counterpoint to Bismarck. The strategy paid off, writes Bonnell, as Lassalle festivals created anchor points for working-class sociability and identity.

In Chapter 2, Bonnell confronts the question of why the SPD's Reichstag deputies voted for war credits in August 1914. Blame is traditionally meted out in two directions: party leaders were swayed in favor of militarism and thus abandoned their principles, and deputies represented the nationalist mentality of their socialist constituents, suggesting that the party had failed to educate its members in internationalism. Bonnell argues first that the party leadership did not simply cave to militarism: he points to a parallel development during the Franco-Prussian War, when the fight against Napoleon III was seen as a form of international solidarity since French workers would benefit from the tyrant's defeat. (Once Napoleon was defeated and the conflict became a war of conquest, the party leadership swung against a continuation of hostilities.) In 1914, fighting the tyrannical tsar seemed equally worthy. Bonnell then draws on police surveillance records to show that rank-and-file workers talked in internationalist terms as they socialized in everyday life. Bonnell points to skilled artisans as one explanation for this internationalism: rather than contaminating the ranks with a petit-bourgeois competitive and patriotic mindset (as is sometimes argued), the fact that artisans travelled and had ties abroad gave them a greater identification with workers in other countries. Bonnell thus argues against the view that a creeping nationalization of the proletarian masses led to the miscalculation of 1914.

The book's other chapters give similar counter-readings to argue that the party was, in fact, remarkably successful in its mass mobilization of workers. In Chapter 5, Bonnell demonstrates that proletarian soldiers were largely anti-militarist. Workers commonly expressed resentment of the authoritarian military structure, rather than simply romanticizing military adventure (although some did that too). As a result, military authorities actively avoided pooling socialist recruits together in units to prevent their agitation from infiltrating the ranks. If the party couldn't always prevent young recruits from military enthusiasm—even though it actively tried—this was largely a structural problem: because army recruits were well below the voting age, they often had little direct political experience at the time of their enlistment. In Chapter 6, Bonnell counters the critique—based on sales figures and lending-library statistics—that workers rarely read Marx, instead pointing to other ways that the party spread socialist ideals among the rank-and-file, including the party's extensive pamphlet literature, the highly popular periodicals Der Wahre Jakob and Der Süddeutsche Postillon, and speeches at the party's mass meetings. In Chapter 7, Bonnell addresses the charge that the SPD's social organizations were petit bourgeois in nature as they often focused on entertainment rather than serious political engagement, and that they mimicked the vacuous offerings of the mainstream culture industry as a form of negative integration into bourgeois norms. Instead, Bonnell argues that these social organizations and cultural events created a robust proletarian identity that made mass political mobilization possible; they also provided practical opportunities for party functionaries to gain organizational experience.

Workers’ attitudes towards labor, republicanism, and economic policies round out the other chapters, again with a focus on how the party joined experiences on the ground with political theory into effective political campaigning and mobilization. These wide-ranging and fascinating topics are contained in a relatively slender volume: Bonnell's goal is to move the goalposts on a number of vital issues, not to provide a comprehensive monograph on any one. Even so, the chapters provide a succinct review of the relevant arguments as well as rich primary source evidence in individual cases, with an excellent use of police records in the Landesarchiv Berlin in particular. The book's concise organization is effective in giving a sense of the party's successes, and for scholars in the field, the volume will surely raise fruitful new questions and stimulus for further research. The book's summaries of scholarly debates and pithy overview of SPD history also promise to be useful to graduate students and scholars new to the field.