Long before the tragedy of George Floyd, long before Black Lives Matter protests erupted in American cities, Shannen Dee Williams had made a name for herself as she uncovered a neglected and sobering chapter in US Catholic history. I personally recall a captivating presentation she gave back in 2016. I was not alone in the audience to learn with great fascination (and embarrassment) how the vast majority of American Catholicism's venerable religious communities and their institutions were built on an undeniably racist foundation, on policies that rejected applicants of colour without scruple. The most gripping and original element of Williams's lecture was her collection of interviews of former Black sisters, with a mission to preserve fragile memories before they were lost to the silence of the grave.

Her promised book has now appeared, and it does not disappoint. What Williams has accomplished in almost fifteen years of research rises to the level of Cyprian Davis's seminal work on Black Catholicism in 1990. Some might say it transcends this predecessor, as Williams challenges not only narratives of US Catholicism but also American and Black history. Like Davis, Williams covers multiple centuries with impressive breadth, a survey that succeeds in ‘historical recovery and correction’ (p. 15). Unlike Davis, however, Williams provides unparalleled original research into the lives of Black Catholic women religious, both those who remained in the convent and those who left, a record of countless interviews and archival discoveries that consumes almost a hundred pages of endnotes. Davis gave future scholars a map of Black Catholic history; Williams has bequeathed a three-dimensional map of forgotten Black Catholic lives, charting both a general overview while plumbing the depths of biographies and religious communities in a manner never done before. Davis and others have focused on priests and laymen; Williams poignantly argues, ‘Long before there were Black priests in the United States, there were Black sisters’, sisters whose struggles and activism not only predated those of Black Catholic priests but also, in Williams's telling, exceeded the dedication, suffering and perseverance of better-known men (p. 10). Subversive habits recovers an eclipsed history of Black women in America, women fitting neither Protestant nor secular categories and abandoned by their fellow Catholics.

And the history jars as Williams writes with tenacious honesty. The reader is forced to confront the dark, inescapable reality that ‘white supremacy’ cannot be confined to slaveholders, the KKK and backwater bigots. The same racism behind burning crosses consumed the practices and protests of White American Catholics, in the North and the South: be it the exclusion from White immigrant convents based on one's Black skin; be it the dress or habits of the nation's earliest Black sister communities; be it the backdoor education of Black sisters to meet state accreditation standards (complicated by the Catholic University of America's decision to bar Black students throughout the 1920s); be it the decision of Black women to learn French and find admission in Quebecois communities when American doors remained closed; be it White parents’ vitriol hurled at the Black nuns tasked with desegregating Catholic parishes and schools; be it the decisions of White diocesan boards to close growing Black Catholic inner-city schools (with clear archival data belying shallow justifications); be it the scepticism and even misogyny surrounding the formation of the National Black Sisters’ Conference (NBSC) in 1968. But Williams's honesty resists any ahistorical agenda. The book excels in the author's ability to outline complexity in the story of Black sisters. For instance, White communities receptive to Black novices harboured diverse opinions about the NBSC in relation to Black Power movements. The NBSC itself championed the virtue of celibacy as an evangelical tool while remaining sceptical of progressive White sisters’ motives for racial justice alongside calls for women's ordination. Later decades witnessed many ardent NBSC members leave the sisterhood, some because of Catholic misogyny, others simply from burnout. Whatever patterns Williams notes, the reader concludes that no two stories are alike, that one must appreciate first and foremost that the history of ‘Black nuns’ is not Hollywood fantasy or tragedy. The history is about individual lives, not nameless faces in veils, women with a personalised conviction that their faith and Church was and is far richer, more diverse and more deeply universal than any Bing Crosby screenplay or Whoopi Goldberg musical.

Overall, Williams provides an essential text for conversations about race, gender and religion in American history. Scholars in sociology, theology, political theory and feminism should also take note of Williams's research. Some historians may question the book's fairness in its assessment of Black Catholic bishops’ ostensible betrayal of Black Catholic activism (Williams oddly omits any reference of Wilton Gregory) or its sharp criticism of Katharine Drexel and her religious order. Nevertheless, any future history of US Catholicism will need to reference Williams's work if one is to take it seriously. Subversive habits alters the landscape of American religious studies and Catholic studies. For Catholics, the book offers critical context for current efforts to canonise Mary Lange, Henriette Delille and Thea Bowman (complementing and nuancing the concurrent cause for Augustus Tolton). Christian or not, readers will fail to forget the lives that leap from the book's pages, from Sister Mary Antona Ebo (d. 2017) and her presence in Selma to Dr Patricia Grey (formerly Sister M. Martin de Porres) and her reconciliation with the White religious community that originally rejected her. Williams breathes life into a tragic and forgotten past through stories of resilient sacrifices, lessons of love from the dead and the living.