Debra Blumenthal's Enemies and Familiars: Slavery and Mastery in Fifteenth-Century Valencia should mark a turning point in the historiography of Mediterranean slavery before the Atlantic slave trade developed. In her coverage of rationales for enslavement in fifteenth-century Valencia, the mechanics of slave sales, the labor slaves performed, their actions in households and Valencian society, and the attainment and consequences of free status, we learn that slavery in Valencia had much in common with slavery elsewhere in the Christian Mediterranean. The differences — the degree of color prejudice, and the prevalence of domestic slavery, for example — point toward the racialized slavery of the Western hemisphere without actually providing a map that leads there. Blumenthal commendably discourages further search in Valencia for the “roots” of racialized slavery and racism. From here on, scholars of slavery in the late medieval period must make their subject its own frame of reference. Freed from the burden of the future, Mediterranean slavery offers medieval and early modern specialists their very own trans-take-your-pick field of operations, where the possibility of enslavement threatened all Christians, Muslims, Jews, and sub-Saharan Africans alike.

However, Enemies and Familiars inadvertently draws attention to a central question requiring an answer, the lack of which unsettles the foundation of Blumenthal's conclusions. How prevalent was slave-owning in the Christian cities and kingdoms whose merchants dominated the trade in slaves? In a work based on notarial and court records, Blumenthal twice allows the reader to see her data clearly. In the only table of quantifiable data in the text, she tabulates the prices of slaves purchased in Valencia between 1420 and 1498 according to gender and ethnicity. As the footnote in which the table appears makes clear, she makes a fundamental mistake of conflating the sales of slaves at wholesale prices with retail sales and resales of slaves. The difference matters because we should not assume that the demand for slaves in Valencia kept pace with the involvement of Valencian merchants in export trade. Indeed, according to the same table, all slave prices fell by at least half their value between 1420 and 1498, the period preceding the rise of the Atlantic slave trade. Remarkably, Blumenthal does not account for the drop in prices her own data shows. In an appendix, she extracts information, such as gender, from formal demands by slaves for their liberty. Over a period just short of a century, she found a total of ninety-four demands for liberty. Her samples are not only small, but without some idea of the percentage of the Valencian population slaves represented, they mean little. In the first footnote of the first chapter, Blumenthal dispenses quickly with the issue of slave numbers by referring to two other scholars’ estimates, based on the records of the Crown and bailiff general, that the slave population in Valencia might have amounted to about ten percent or possibly more of the total population. Were any of those slaves assessed by the bailiff general intended for export? Did those other scholars’ estimates apply to all of the fifteenth century or only a portion of it?

The small size of Blumenthal's samples and the fall in slave prices suggest that, as was the case in Italy in the same period, the demand for slaves in Valencia declined over the fifteenth century. Taking that possibility into account would have led Blumenthal to more sophisticated and useful insights. Because her interpretation rests on a thin foundation, she misses several opportunities to break new ground in her monograph. For instance, she might have framed her discussion of the participation of professional brokers (corredores d'orellà) in the resale of slaves within the growing literature on secondhand dealers and the recirculation and shifting values of consumer goods in early modern economies. Instead, her reflections on slaves as tools of honor lead us down a short road that ends in a cul-de-sac. In the end, however, although Blumenthal's neglect of the broader economic and demographic context dilutes the meaning she attributes to the interactions between slaves and masters, she has made a useful contribution to our understanding of slavery in the Iberian world.