In his introduction to Twelve Years a Slave, American historian Ira Berlin contextualizes the historic significance of the memoir. Berlin explains that Northup’s memoir is unique among slave narratives is its exacting precision, from the living conditions in the slave cabins to the exhaustion of laboring in the fields to the brutality of the beatings he received. These details allowed Northup to debunk prevalent arguments Southern apologists made at the time, including the argument that free life in the North was no better than enslavement in the Deep South.

Northup’s account was distinct from previously published nonfictional slave narratives such as Narrative of the Life of Frederick Douglass, an American Slave because it featured specific, verifiable evidence, including precise place names and dates. Furthermore, the memoir featured complex socioeconomic criticisms of slavery as a capitalist institution, exploring not only the cruelty of slave masters, but also the ways in which they justified their practices as part of a broader system. Thus, the bestselling text was an invaluable tool for abolitionists.

The original 1853 editor’s preface was written by David Wilson, a white lawyer, writer, and editor who worked with Northup to compose Twelve Years a Slave.