Robert Michels is a figure well known to students of European political and socialist history. His most important work, Political Parties (1911), is still widely read for its analysis of the development of political institutions, and his theory of the “iron law of oligarchy” remains an important reference point in the scholarly discourse on the relationship between rank-and-file membership and the leadership of modern democratic political parties. Michels is also known for his turn from revolutionary syndicalism, or the left wing of German social democracy, to fascism, a shift that is often explained by reference to his disillusionment with mass democracy. While there is a very substantial literature on Michels, there has been no full-length study in English in over half a century, and scholars have neglected a substantial portion of his oeuvre. Andrew Bonnell aims to address this lacuna by focusing on the decade from 1900 to 1910, the most fertile period of Michels's career. This narrow focus allows him to provide “a more thoroughly contextualized analysis of his intellectual development.” Ultimately, he argues that, rather than viewing Michels as a fundamentally disillusioned democrat, “it is important to appreciate Michels's essentially agonistic understanding of politics and his sense of political life as representing an arena that would allow exceptional individuals, like himself, to demonstrate their worth” (12).

Bonnell's study is organized into two parts. Part I provides a biographical overview and focuses on Michels's engagement in socialist politics in Germany, Italy, and France. Born in Cologne in 1876 into an upper-middle-class family of French-German Catholics, Michels was educated at the French Gymnasium in Berlin and then, after a stint in the army as an officer cadet, at the Sorbonne and the Universities of Leipzig, Munich, and Halle, where he completed his doctorate in history. Initially drawn to social democratic politics, the cosmopolitan young scholar aimed to pursue an academic career in Germany while simultaneously engaging in socialist activism. His inability to do so within the confines of the conservative German Empire ultimately resulted in his move to more congenial Italy, where he joined the faculty of the University of Turin in 1907. He moved to the University of Basel in 1914 but, attracted by the charms of fascism, eventually accepted a chair at the University of Perugia in 1927.

Writing in three languages, Michels produced hundreds of essays, reviews, and political reports for the socialist and non-socialist press as well as for academic journals. He also built up a transnational network of personal and political contacts and developed an extensive correspondence with a wide range of figures such as Karl Kautsky and Max Weber in Germany, Georges Sorel in France, and Vilfredo Pareto in Italy. Bonnell has mastered this enormous trove of material as well as the large secondary literature on Michels and his various milieus. On this basis, he effectively traces Michels's intellectual and political evolution in the pre-1914 era.

Bonnell shows how Michels entered social democracy as a member of its left wing. Although he did not engage Karl Marx's economics systematically, he vehemently opposed Edward Bernstein's “revisionist” criticism of Marxist “orthodoxy,” criticized the German trade union leadership's cautious attitude toward the general strike, and insisted that socialists take a much stronger line against German militarism and colonialism. Michels grounded his politics not in historical materialism, but rather in an ethical outlook that idealized class struggle and made him sympathetic to decentralized and action-oriented French syndicalism. Within a few years, he grew increasingly frustrated with German social democracy's emphasis on party building and electoral politics and by his inability to gain a post in the reactionary German academy. He attempted to resolve these dilemmas by moving to Italy, where, under the influence of such thinkers as Pareto and Gaetano Mosca, he developed his increasingly conservative critique of mass democratic parties.

In part II, Bonnell analyzes Michels's relationship to “modern ideas and movements,” and it is here that the reader gains a better understanding of how his later affinity for fascism stemmed not from any sudden turn, but rather was rooted in many of the ideas he expressed while still a socialist. Michels wrote on a wide variety of issues, including feminism and sexual politics; the relationship of intellectuals, masses, and leaders; the differences between internationalism, patriotism, and nationalism; as well as race and ethnicity. His views were often contradictory, and Bonnell shows that they were derived, in part, from Michels's own temperament of “ethical superiority” as well as his time and place. For example, his view of the capabilities of the masses were increasingly influenced by the racial ideas of Italian thinkers on the left, “who articulated a belief in natural-biological hierarchies” among different social groups. And while Michels remained unremittingly critical of the “anachronistic, feudal reactionary structures” and colonial policies of the modernizing German Empire, he became a supporter of Italy's colonial expansion (266-267).

Bonnell writes well and explains Michels's evolving ideas clearly and succinctly. One wishes, however, for more biographical material to enhance Michels's lived – rather than intellectual – context, especially his relationship to his wife, Gisela Michels-Lindner, who apparently shared his political proclivities and facilitated his work. Taken as a whole, however, Bonnell presents a thorough and compelling picture of a leading thinker and critic of early twentieth-century socialism.