Since the 2007 bicentennial of Britain's abolition of its Atlantic slave trade in 1807 the University of Cambridge's Centre of African Studies has sponsored an annual series of state-of-the-art lectures on this much contemplated event. Derek Peterson, who directed the Centre at the time of the inaugural lectures, in this volume attempts to integrate Africa into what had often been an event more noticeable in the European Atlantic than in Africa. Only one other, among the outpourings of 2007, has been similarly oriented: the large gathering at Elmina in Ghana sponsored by the Omohundro Institute of Early American History and Culture (in Williamsburg, Virginia, in the United States). The bicentennial of Britain's abolition and of the US prohibition of its own trade in the same year was otherwise strikingly unremarked in the United States. The emphasis in this work on abolitionism and ideologies complements the political and economic accents on slave trading and slavery, in Africa as well as around the Atlantic basin, in the Omohundro proceedings.

Here the all-star cast of contributors starts with John Thornton's characteristically thoroughly documented consideration of the long-standing question of how the slavers in Africa may have regarded the ethics of selling people to Europeans. Thornton phrases his answer in terms of the quite artificial contrast proposed years ago between ‘political’ slaving for the purposes of African state leaders and ‘economic’ slaving for the profit of the same authorities. It is another question whether this contrast in abstractions is a question of political ethics, as he puts it, in the quite distinctive and novel sense developed in the northern Atlantic, through the discourse of abolitionism itself in significant part. Boyd Hilton considers these political ethics in two ways: (1) the politics of the bicentennial excesses in 2007; and (2) an under-appreciated deeply religious dread of divine punishment for the emerging modern abandonment of God, or as he phrases it, the liberal altruistic secular humanism normally credited with ending slaving, which key conservative politicians in Britain experienced as sin.

Christopher Leslie Brown, Philip D. Morgan, Seymour Drescher, and Robin Law then turn more directly to the central theme of the volume, the links between militant British abolitionism after 1807 and what became outright armed imperialism in Africa by the end of the nineteenth century. Brown considers how British strategists turned to promoting economic investments in commodity production in Africa as they contemplated ‘Empire without America’ after 1783 to turn the usual sequence of abolitionism leading to imperialism on its head, finding planners – including Equiano – to dreams of empire in Africa as a rationalization for ending the dependence of American colonies on Atlantic slaving without grievous economic damage to Britain. Morgan amplifies recent appreciation of the pragmatics of the era, political and economic, by treating abolitionism as one strategy with many implications, which converged momentarily in 1807 to secure the key – only retrospectively momentous – vote in Parliament. With numerous cautions against the noble teleologies that have pervaded this field – from the altruistic pretensions of empire punctured decades ago by Eric Williams to more recent claims that rebellious slaves freed themselves through the challenges they presented to nervous owners and their friends in Parliament – he joins Hyde in finding backing, not inconsistent with the international maneuvering toward empires in the era, for the cause among conservatives. For decades, Drescher has been perhaps the leading complicator of the story, in several registers, from economic to ideological. Here he emphasizes the anti-imperial strain in British policy, in the sense of territorial acquisition and occupation in Africa, through a string of growing commitments – the Sierra Leone settlement, the Asante war of the early 1820s, the Niger expedition of 1841, right down to the 1884–5 Congress of Berlin. His logic seems to rely mostly on the contemporaneity of abolitionism and this strategic reserve to conclude that abolitionism may have conditioned but could not have caused later imperial conquests in Africa. Law comes to a contrasting conclusion regarding other issues surrounding acquisition of African territories in the era of Britain's suppression of Atlantic slaving. Citing interventions in Dahomey and at Lagos in 1851–2, he uses discussions of the legal construction of these actions to demonstrate a key sacrifice of prior respect for the sovereignty of African political authorities to discounting them as outlaw slavers standing outside the emerging framework of international law; anti-slavery was thus established early as among the grounds on which European nations would proceed to carve up the continent in the 1880s.

Jonathon Glassman concludes the volume with a very subtle contemplation of the epistemological implications of the book's attempt to link two abstractions – abolitionism and imperialism – in the implicitly causative ways pursued by most of the contributors to it. His test case of the broad historical relationship between ideas, or ideologies, and action is the Zanzibar anti-‘Arab’ riots and near-genocide of 1961, in the then (briefly) planned island nation, subsequently part of Tanzania. Abolitionist Christian missionaries, among others, had memorialized the island's Omani planters as ‘Arab slavers’, and various partisans in the extremely complex and intense politics of an incipient nation had invoked this image in mobilizing descendants of the mainland Africans in fact brought to Zanzibar in the nineteenth century through slaving to massacre other people memorialized as ‘masters’. But not so fast: Glassman brilliantly demonstrates that ideas in themselves don't have consequences. Rather, a cacophony of local intellectuals and politicians made chaotic uses of these and other memorializations of slavery and abolition, and many other ideas, in agitating anxious incipient citizens to levels that turned into a moment of extreme violence. His concluding admonition to historians, ‘to understand, with as much empathy as possible, what historical actors have made of the variety of inheritances left them’, might well become the anthem of the coming historicization of the continent's past.

Editor Peterson's introduction, beyond the conventional summary assessments of the contributions to follow, highlights other African intellectuals' rhetorical resort, in Uganda, to abolitionist discourse in Nyoro pleading with British colonial authorities in the 1930s for restoration of their ‘lost counties’; fortunately, he resists amplifying this strain in the politics of the time to causative status. I have given disproportionate space to Glassman's demonstration of the distinctive epistemology of the historical discipline because it speaks most directly to the readership of this journal. But the ideological considerations that other contributors to this volume raise are also more than worthy of the attentions of historians of Africa. Many of our sources are couched in, or were written to propagate, these essentially European processes of creating modernity. We project them onto Africans at our considerable peril, and we can avoid these temptations only by recognizing them for what they are. Each of the other contributors adds Africa-oriented elements to discussions heretofore neglectful of Africa's presence in Atlantic and world history. As a field, African history, as here, is attracting appropriate attentions from the leading historians in the fields heretofore central to the discipline. This book nicely advances that cause, and we can hope for more of the same from the Cambridge centre that produced it.