Curtin, who was awarded a MacArthur Foundation grant in 1983, died June 4 of pneumonia at Chester County Hospital in West Chester, Pa.
A fellow of the American Academy of Arts and Sciences, Curtin applied more rigorous and scholarly methods to the study of the slave trade and brought the topic to the attention of a wider academic audience. He published more than a dozen books and co-founded the department of African languages and literature at the University of Wisconsin, which the American Historical Assn. said was the first in the United States.
Writing in an American Historical Assn. blog post, Pillarisetti Sudhir said Curtin "broke away from the dominant Eurocentric models of historiography of other continents to create a critical and pioneering body of scholarship on Africa, the Atlantic world, the British empire, and comparative history."
His 1969 book, "The Atlantic Slave Trade: A Census," estimated that 20 million to 30 million Africans were loaded on slave ships, but only 9 million to 12 million survived the Atlantic crossing.
While documenting the history of the trade, Curtin questioned the importance of Goree Island, Senegal, which has become a major tourist draw as the "door of no return" where millions of Africans were shipped out as slaves.
"The whole story is phony," Curtin, a retired history professor at Johns Hopkins University, told the Baltimore Sun in 2004. Although the spot functioned as a commercial center, it was never a key departure point for slaves, he said, adding that most Africans sold into slavery in the Senegal region would have departed from thriving slave depots to the north or south.
Curtin's work was not limited to the study of the African diaspora. He wrote about the influence of disease on European colonization, imperialism in India and the ecological history of the Chesapeake Bay. He also wrote a memoir, "On the Fringes of History" (2005).
Curtin was born in Philadelphia on May 22, 1922, and grew up in Webster Springs, W.Va. He served in the Merchant Marine during World War II. He graduated from Swarthmore College and received a master's degree in history in 1949 and a doctorate in the field in 1953, both from Harvard University. After teaching at Swarthmore, he joined the University of Wisconsin in 1956 and moved to Johns Hopkins in 1975, where he remained until retiring in 1998.
His career was not without setbacks. In 1995, he wrote an opinion article for the Chronicle of Higher Education headlined "Ghettoizing African History" that said many jobs in the academic field of African history were being reserved for black scholars, discouraging nonblack scholars from taking up the field. He also said he feared that the immigration of African-born scholars meant that white scholars of Africa would be pushed out of the field. Many of his colleagues objected to the racial implications of the article.
Among his honors were a Guggenheim Fellowship and presidency of the American Historical Assn.
His marriages to Phyllis Curtin and Patricia Romero ended in divorce.
Survivors include his wife, Anne Curtin, and their three sons; three grandchildren; and two brothers.
Sullivan writes for the Washington Post.