Dwight Lowell Dumond's Antislavery
1 is available at archive.org. The quote about 100 million is on the first page of chapter 7 and does not give a reference for that figure.
SlaveVoyages, a database that is the result of years of international research, has statistics and specific information on individual ships involved in the transatlantic slave trade based on records from the ships themselves. For some of the later ships, the names of the enslaved persons were recorded and are available in the database.
According to this database, approximately 10.7M enslaved persons embarked from Africa. Of these, only 9.2M disembarked, a mortality rate of 12% from the voyage alone. 50% went to the Caribbean, 35% to Brazil, about 10% to mainland North America and Spanish mainland Americas, and the remaining 5% to Europe and other destinations.
At first glance, looking at the ~10 million figure given for the number of Africans removed across the Atlantic, the 100 million figure would appear to be off by a factor of 10. However, look again at the Dumond quote:
The denial of emancipation by conversion to Christianity had shifted the basis of slavery from heathenism to race. The consequences were frightful. It unloosed on Africa for generations a terror unequaled in human history--a terror that did not cease until 100 million human beings perished.
Although the chapter opens with a sentence about "slavery in the United States," this particular quoted passage is referring to the effect on Africa and Africans -- for generations, not specifically those who were explicitly transported against their will to the United States, but all of those who were removed from Africa and their enslaved descendants.
Also, the quote does not say that 100 million were transported; it says that 100 million perished. This number includes the ~10 million forcibly removed from Africa and taken to any destination over 350 years, plus all of their descendants who died while enslaved.
We probably cannot follow all of the enslaved persons to all of their destinations, so as a proxy, let us look at the numbers for the United States.
Enslaved persons were enumerated in the United States census between 1790 and 1860. The aggregate numbers are available from census.gov.
||Enslaved Persons (in thousands)
These figures are only snapshots in time; they don't give us a total number over time. However, it is likely that none of the 698,000 persons enumerated in the 1790 census were still alive for the 1860 census. Also, note that slavery had existed in mainland North America for 171 years before the first census.
According to SlaveVoyages, 365,713 people were taken from Africa to mainland North America between 1655 and 1860 (1619-1654 were from intra-American voyages). The number of enslaved persons in the 1860 U.S. census, 3,951,531, is a little more than 10 times the number who were removed from Africa and taken to mainland North America.
There was some intra-American trade in enslaved persons, about 450,000 according to SlaveVoyages, and the sugar plantations of the Caribbean are known to have been especially deadly, but let us assume anyway that the 10x ratio of transported Africans to final number of enslaved persons applies everywhere.
Using that 10x ratio, it is conceivable that the approximately 10 million Africans removed over 350 years could have resulted in a population of 100 million enslaved persons, hence 100 million deaths, across the Caribbean, Brazil, mainland North America, Spanish mainland Americas, and other locations.
Thus, it seems that Dumond's figure of 100 million deaths over 350 years across the entire Americas region may be accurate, but it was misinterpreted by Malcolm X to be the number of Africans uprooted from their continent and further misinterpreted by others as the number of Africans brought to the United States.
1The hyphen appears only on the front cover. On the title page and the numbered pages, the title is not hyphenated.