Born in Westmoreland, Jamaica, Cooper grew up in Kingston, Jamaica and migrated to Toronto in 1980. She holds a Ph.D. in African-Canadian history with specialties in slavery and abolition. Her dissertation, "Doing Battle in Freedom’s Cause", is a biographical study of Henry Bibb, a 19th century African American abolitionist who lived and worked in Ontario. She also has expertise in women's history and New France studies.

Cooper still lives in Toronto, where she currently teaches in the departments of History and Women's Studies at the University of Toronto. She is a winner of the Harry Jerome Award for professional excellence.

She has published four books of poetry, including Memories Have Tongue (1994), one of the finalists in the 1992 Casa de las Americas literary award. She is the co-author of We're Rooted Here and They Can't Pull Us Up: Essays in African Canadian Women's History (1994), which won the Joseph Brant Award for history. She has also released two albums of her poetry.

Her book The Hanging of Angelique (2006) tells the story of the black slave Marie-Joseph Angelique who was executed in Montreal at a time when Quebec was under French colonial rule. It was shortlisted for the 2006 Governor General's Literary Award for non-fiction.