According to Library Journal, this is "the definitive bibliographic reference covering the history, culture, area studies, and current affairs literature of the United States and Canada, from prehistory to the present." Includes Slavery & Abolition, described by your instructors as "a leading journal, with a strong comparative emphasis."
Indexes scholarly literature on the history of the world (excluding the United States and Canada) from 1450 to the present. Coverage is broad, so the database is also useful for topics in other disciplines (e.g. religion, anthropology, or political science).
Full-text articles from more than 100 scholarly journals published by Carnegie Mellon, Duke, Indiana, Johns Hopkins, MIT, Oxford and Penn State university presses, as well as the presses of the Universities of Hawaii, Texas, and Wisconsin.
Includes the Cambridge World History of Slavery. Also includes regional and economic histories on America, Latin America, and Africa. Perhaps the best reference work available for your paper; certainly a good place to get an overview of your topics.