Between 1858 and 1862, Joseph Oppenheimer walked the streets of “darkest London” to spread the Christian message to “some of the poorest of London's poor” (xxiii). Working on behalf of the London City Mission (LCM), Oppenheimer recorded his encounters with the inhabitants of Dudley Street in the parish of St. Giles's-in-the Fields in a journal. His observations, which might appear somewhat perfunctory at first glance, give new perspectives on the living conditions of the poor and their attitudes toward religion. Donald M. Lewis rescues this rich source from obscurity in In Darkest London, which contains not only a transcription of the journal but also helpful contextual information about Oppenheimer, the LCM, and St. Giles. The result is a valuable resource that enriches understandings of the social and religious lives of London's poor.

In Darkest London is comprised of four sections: background on the LCM, Oppenheimer, and Dudley Street (“The Sower's Work, The Sower, and The Sower's Field”); the journal itself, which covers the period between September 1861 to May 1862 (“The Sower's Words”); a study of the social groups that Oppenheimer encountered (“The Sower's Soil”); and lastly, an assessment of Oppenheimer's impact (“The Sower's Harvest”). In the first section, Lewis uses a variety of sources to reconstruct the life of Oppenheimer and the religious and social landscapes of Victorian London. City missionaries like Oppenheimer were ubiquitous figures in St. Giles; they went where others feared to tread. Oppenheimer is a unique figure in many ways. As a German Jewish immigrant who recently converted to Protestantism, he was an outsider and foreigner, but as Lewis highlights, this marginal status in many ways constituted an advantage that aided his work. In his role as a city missionary, Oppenheimer interacted with diverse social groups, from Irish Catholics and Jews to prostitutes. While Oppenheimer's purpose was to evangelize and distribute religious tracts, his journal reveals that he actually fulfilled many roles, from apologist to amateur social worker. The inhabitants of St. Giles were in desperate need of assistance, but they wanted practical, not spiritual, aid. For many of them, the challenges and precarity of daily existence left little time for religion. A theme running throughout the book—and one apparent from the section titles of the book—is Oppenheimer as a sower; his role was to sow the seed in the field of Dudley Street and St. Giles and watch it grow. However, as Lewis notes, he often encountered “stony ground,” including illness and skepticism, indifference, and even threats of violence, and performing this work required great perseverance.

In Darkest London not only sheds light on this relatively unknown figure and source but is also useful as a research and pedagogical resource. This book would be an effective text in a variety of undergraduate and graduate courses from religious history to urban history to historical methods. Oppenheimer's journal complements and supplements more well-known works on the poor in Victorian London, namely those by William Booth and Henry Mayhew. Unlike Mayhew and Booth, however, Oppenheimer remains a largely anonymous figure. Beyond his journal, little documentary evidence about him exists. Yet Lewis is able to piece together a portrait of the missionary and his time as a city missionary through the use of a wide range of sources, including London City Mission Magazine, censuses, wills, parliamentary records, religious tracts, personal biographies, minutes of the LCM board meetings, and illustrations. For instance, he uses census, marriage, and baptismal records to shed light on what happened to some of the occupants of Dudley Street after the brief moment in 1861–1862 when they crossed paths with Oppenheimer and, in doing so, gives the reader a fuller, more nuanced picture of the world of St. Giles. Through the incorporation and contextualization of these various sources, In Darkest London provides a valuable study of the complexity and subjectivity of historical research and reconstruction.

In Darkest London is not just an effective pedagogical tool but also informs understandings about a range of topics from class relations to prostitution to Victorian evangelicalism. While the LCM was less influential than later organizations—namely the Salvation Army—Lewis draws attention to the often-overlooked impact of the LCM's work, particularly the importance of the city missionaries’ first-hand knowledge of the daily life of the poor and the vital role this information played in bringing social problems to the attention of British politicians and society. The concerted efforts of the LCM moreover demonstrate the intensity of evangelical efforts among poor. As Lewis observes, largely because of the paucity of sources, what the poor heard or said about religion has been overlooked (xxi). However, the voices of the poor—and particularly their desperation—emerge from the pages of Oppenheimer's journal, such as when he records his conversation with an Irish woman who confides in him: “I heard a great deal about heaven & hell, but I am sure I have got my hell here I need not have another I am sure if anyone ought to go to heaven I ought” (120). Through this interesting and perceptive study of Oppenheimer and his world, Lewis provides new insights into how the poor understood and engaged with religion and the nature of religious discourse in this period.