Gump's research has focused on the history of South Africa, Britain's imperial experience in its settlement colonies, and the comparative history of indigenous South Africans, Native Americans, and the New Zealand Maori. His book The Dust Rose Like Smoke: The Subjugation of the Zulu and the Sioux (1994), a History Book Club selection, compares the military subjugation of the Zulu and Lakota Sioux from the perspective of these indigenous societies. Gump has also studied the ways in which colonized peoples renew their cultures in the wake of military conquest and forced acculturation. His publication "A Spirit of Resistance: Sioux, Xhosa, and Maori Responses to Western Dominance, 1840-1920," won the Koontz award for best Pacific Historical Review article in 1997. Other publications have appeared in The Historian, African Economic History, Western Historical Quarterly, Journal of World History, and Safundi: The Journal of South African and American Studies. His current book project is a comparative study of the state-sponsored destabilization campaigns directed against the American Indian Movement and the African National Congress in the latter third of the twentieth century.