Following stints at
North Central College (1982–1987) and
Harvard University (1987–1989), Blight taught at
Amherst College from 1990 to 2003. In 2001, he published
Race and Reunion: The Civil War in American Memory. It "presented a new way of understanding the nation's collective response to the war, arguing that, in the interest of reunification, the country ignored the racist underpinnings of the war, leaving a legacy of racial conflict." The book earned Blight both the
Bancroft Prize and
Frederick Douglass Prize. After being hired by Yale in 2003 and teaching as a full professor, in 2006 Blight was selected to direct the Gilder Lehrman Center for the Study of Slavery, Resistance and Abolition. His primary focus is on the
American Civil War and how American society grappled with the war in its aftermath. His 2007 book
A Slave No More: Two Men Who Escaped to Freedom, Including Their Own Narratives of Emancipation provides context for newly discovered first-person accounts by two African-American slaves who escaped during the Civil War and emancipated themselves. He also lectures for
One Day University. In Spring 2008, Blight recorded a 27-lecture course,
The Civil War and Reconstruction Era, 1845–1877 for
Open Yale Courses, which is available online. Blight wrote
Frederick Douglass: Prophet of Freedom, released in 2018, as the first major biography of Douglass in nearly three decades. One reviewer called it "
the definitive biography of Frederick Douglass" and another heralded the book as "the new Frederick Douglass standard-bearer for years to come." It earned the 2019
Pulitzer Prize for History and the 2019 Gilder Lehrman
Lincoln Prize. Contributing to the anthology
Our American Story (2019), Blight addressed the possibility of a shared American narrative. He cited Frederick Douglass's 1867 speech titled "Composite Nation" calling for a "multi-ethnic, multi-racial 'nation' ... incorporated into this new vision of a 'composite' nationality,
separating church and state, giving allegiance to a single new constitution, federalizing the
Bill of Rights, and spreading liberty more broadly than any civilization had ever attempted". Blight concluded that although the search for a new unified American story would be difficult, "we must try". In July 2020, Blight was one of the 153 signers of the "Harper's Letter", published in ''Harper's Magazine'' and titled "
A Letter on Justice and Open Debate", which expressed concern that "The free exchange of information and ideas, the lifeblood of a liberal society, is daily becoming more constricted." In 2020, David Blight was commissioned by the then president of Yale College
Peter Salovey to form a research group on "the history of Yale and slavery." In 2024, Blight published
Yale and Slavery: A History, in which he found that "A multitude of Yale University's founders, rectors and early presidents, faculty, donors, and graduates played roles in sustaining slavery, its ideological underpinnings, and its power". From 2024 to 2025, Blight served as the President of the Organization of American Historians (OAH), the largest professional society for teaching and researching American history in the United States. ==Awards==