By the time the Capuchins arrived in the seventeenth century, Kongo had been Catholic for nearly two hundred years. The European mission could not be conversion, then, but reinforcement; the Capuchins sought to establish the sacraments and a line to Rome in a lay-led church already suffused with an enduring, creative, and complex theological culture. In Memorializing the Unsung, Elochukwu Uzukwu uses the framework of this "ancient" Kongo Catholicism to explore European dependence on enslaved Kongo Catholics and the unconscionable Capuchin and Spiritan participation in the slave trade at large—a practice denounced by the lone voices of Capuchin Epifanio de Moirans and Spiritan Alexandre Monnet.

Reconstructing the church that missionaries and Kongo Catholics built together on the foundations of local religion, Memorializing the Unsung contrasts the dignity denied the Kongo Catholics with the freedom they nonetheless performed. Uzukwu is particularly deft in tracing the agency of Kongo elites and laypeople from the fifteenth century through the nineteenth, carefully evaluating their deliberate engagements with southern Europeans, the role of the maestri (translator-catechists) in guiding the faithful, and the ultimate development of a unique theological vocabulary endorsed by the Kikongo catechism.

Without the support and creativity of these unsung lay Catholics across west-central and eastern Africa, Uzukwu shows, the European missions in the region would have failed. Even while enslaved, the Kongo Slaves of the Church and the eastern African Slaves of the Mission served as mediators, co-creators, and reinventors of their world.