A book as rich and complex as The Atlantic Slave Trade. A Census is almost impossible to review in anything less than another book, for it poses problems of evidence, method, and finding on virtually every page. Its immense contribution is a sustained examination of almost all known evidence on the numbers of Negroes moved, the areas from which they came, the regions to which they went, changes in volume of movement during the nearly five centuries of the trade, and the role of each European nation as carrier.
Philip Curtin begins his inquiry by inspecting two chains of estimates that a total of perhaps fifteen million persons were moved in the Atlantic slave trade. Having exposed these estimates as tenuous, he then turns to a third of approximately twelve millions made by Noel Deerr and conducts a systematic reexamination. Curtin approaches the trade from two different viewpoints, its distribution in space and its distribution in time. The first involves determining how many slaves were imported into the islands of European settlement off the African coast, Europe, and each region of the Americas. The second involves determining by periods the annual averages of numbers moved by national carriers.
The firmest kinds of data are actual import figures where they exist, numbers called for in importation contracts, and the carrying capacity of shipping employed in the trade. The fragmentary nature of surviving data and the problems of adjustment for evasion and smuggling require much piecing. Curtin’s estimates for the French slave trade are based essentially upon the excellent runs of data for Nantes, those for the British slave trade upon sample data primarily of Liverpool. A second general category of estimate is that calculated from counts of slave population through adjustments for mortality and natural increase to arrive at the imports necessary to establish that population. Since our information on births, deaths, and sex ratios is scant, the method is correspondingly shaky; but it is a brilliant suggestion for provisionally filling in gaps that could be strengthened by further research. Equally innovative methodologically, but also requiring more buttressing, is the use of analogy in course of development for estimate. The estimates for British Caribbean islands are really based upon the experience of Jamaica.
In the end, Curtin arrives at a total estimate of 9.556 millions moved in the Atlantic slave trade, of whom 175,000 went to Europe and islands off the African coast. Obviously his figures have very wide margins of error, far wider than the twenty percent he hints at, and are probably skewed by failure to include rather than by overestimates. His most striking change is a sharply downward revision of numbers moved to the Anglo-American mainland, which he estimates received only 400,000 Negroes. Equally striking are Curtin’s determinations of survival and increase. The Caribbean plantations led in the consumption of human beings; those of Brazil were second. The most favorable biologically were the Anglo-American mainland colonies, which imported approximately equal numbers of the sexes and encouraged natural increase at a rate approximately equal to that of the white population. Again, a matter not discussed by Curtin, the most important factor may have been climate, for white immigrants to the tropics also had very high death rates. Nevertheless, Curtin has added new significance to an intensely interesting aspect of the comparison between slavery on the Anglo-American mainland and that elsewhere.
Curtin also examines the sources of the slaves in Africa, European preferences in procurement, and the destination of the African regional contingents within the New World. Again he is forced to estimate from remarkably fragmentary data; again his estimates open wide vistas for examining the varying impact of African cultural elements in the New World and the affect of the slave trade on the society, culture, and economy of western Africa. A further major conclusion is inescapable that if Curtin gives anywhere near a reasonable estimate, the demographic impact of the slave trade upon Africa was minimal. However unpleasant the term when applied to human beings, one is forced to think of cropping.
In short, Curtin has written a brilliantly provocative book that should lead to a range of new inquiries.
