The increasingly prominent transnational approach to the history of radicalism in the United States often focuses on interethnic, gender, and border dynamics, as well as important actors, like the women anarcho-syndicalists of the Borderlands, who have been unfairly neglected by historians.Footnote ¹ While this area of scholarship has thrived within the immigration and migration arcs transforming the nation in the early twentieth century, Workers of All Colors Unite begins and ends in the late nineteenth century. The book is clearly transnational but focuses almost exclusively on the ideas of German immigrant men who were socialist movement leaders. Costaguta’s story explores the complexity of debates over race and ethnicity during the early history of the Socialist Labor Party (SLP), which united disparate socialist factions in 1876 to form what became the most important socialist organization of the Gilded Age before being hollowed out by the Socialist Party of America (SPA), founded by Eugene V. Debs in 1901.

The author is primarily concerned with the period from 1876 to 1890, with one chapter on the impact of the Civil War era prior to the SLP at the beginning and one chapter on the decade before the emergence of the SPA at the end. The SLP seems like the obvious choice to study socialism in this period, but it comes with a difficult limitation: up to 90 percent of the membership was German during the main period of the book. “American socialism was thought, spoken, and written almost entirely in German” (3). Because this is a book more about the evolution of ideological debates than about the cultural and social life of the group and its members, the evidence and narrative lean heavily into the writing of the male leadership. This approach would seem retrograde if the author had chosen to focus on strategic debates about the merits of political campaigning versus trade union organizing, a much-worn theme. Instead, we have the first book that attempts to comprehensively trace the evolution of early socialist thought in the United States on the major racial debates of the Gilded Age.

The author stresses that Workers of All Colors Unite uses historical scholarship on whiteness to study “how the German origins of socialists affected their understandings of race” toward the larger goal of “putting debates on race center stage and reconstructing the early history of American socialism through that perspective” (9). This is an important and original rewriting of early U.S. socialism. The key struggle over both ideas and strategy now becomes a split between and within two factions: scientific racialists and internationalists. The first category would be eclipsed after the nineteenth century but was easily the most successful of the two during the Gilded Age. Opposed to the universal class unity message of the internationalists, those who embraced scientific racialism were part of a transnational debate among socialists over the role of Darwinism in the battle against capitalism.

The author lays out this struggle during the early years of the SLP in detail in the second chapter with a focus on the scientific racialists, who were both more prominent at the time and carried on more of a complex intrafactional debate. To demonstrate this complexity, the author develops an intellectual biography of the journalist Adolph Douai. Douai fused pre-Darwinian ideas, including the historical geography of Romantic naturalist Alexander von Humboldt, with Darwin to form a “bricolage theory of human biological transmutation” (62). His research convinced him that through the global migration of peoples, progress up the ladder of development could be rapid, and that it should be encouraged. An opponent of Chinese exclusion, he felt that racial science supported an absolute open-border policy in the United States. Many of his fellows rejected his conclusions and had different, or much less, use for Darwin. Costaguta makes it clear that no single approach to racial theory gained dominance and debate over it remained central to the struggle to define socialism throughout the Gilded Age. Factionalism led to the split of the SLP after just several years, with many of the internationalists leaving to form the International Labor Union (ILU).

With scientific racialism now dominant, but divided and evolving, the author focuses three chapters on the SLP and Chinese immigrants, African Americans, and Native Americans in the period up to 1890. Knowing in advance that the SLP remained an almost entirely German immigrant party during this period prepares the reader for the organization’s failure to achieve ethnic and racial inclusion or gain a nuanced understanding of non-white workers. The most substantive coverage of a nonwhite socialist in the book is a chapter section on Peter H. Clark, an African American activist in Cincinnati who “described socialism as a solution for economic inequalities and racial ones” (108). Costaguta believes that Clark’s work on the economic exploitation at the heart of segregation influenced later African American socialists, such as W. E. B. Du Bois. However, he had little influence on the SLP and did not stay long. The chapter on the SLP reaction to the plight of Native Americans in this period and to the mainstream use of exterminationist language in the press traces a direct causal relationship to “the ways in which socialists progressively replaced scientific racialist discourses of racial inferiority with analyses focused on levels of … social and economic development” (146). However, they still seemed fixed on “ascribing social and cultural attitudes” to a group’s “innate essence” (146).

In the 1890s, the party began to conduct its business in English and it attempted to project a more inclusive image. Under the leadership of Daniel De Leon, the “SLP rejected biology-based scientific racialism … calling it a bourgeois doctrine that justified inhumane social and economic policies by distorting Darwinism” (150). As the world evolved toward socialism, racism “would disappear along with the other injustices suffered by American workers” (150). This turn may have pushed aside the central debate of Gilded Age socialism, but it also pushed race aside and led the SLP to ignore inequality as merely a transitory problem that would naturally resolve. More inclusive imagery and rhetoric did not reshape the SLP membership.

Costaguta makes a convincing case that the transnational ideas inherent to an evolving, immigrant-driven socialism reacting to the U.S. context requires more serious consideration of the Gilded Age, even if the perspective is often exclusively German. If race is to move to the center of our understanding of the evolution of organized socialism in the United States, Costaguta points the way forward from its beginnings.