Questions were often raised about accuracy or authenticity of books about slavery, including slave narratives. Similarities between Northup's book and Harriet Beecher Stowe's novel Uncle Tom's Cabin have been noted by critics. Stowe's book was published a year before Northup's memoir but by the time she published her rebuttal to critics about accuracy, in her Key, she referred to his story, which had been publicized in newspaper accounts. Stowe wrote,
|“||It is a singular coincidence that this man was carried to a plantation in the Red River country, that same region where the scene of Tom's captivity was laid; and his account of this plantation, his mode of life there, and some incidents which he describes, form a striking parallel to that history.||”|
Northup's account confirms Stowe's fictional portrayal of conditions in Louisiana, as the area where Northup was enslaved was close to the fictional setting of Simon Legree's plantation on the Red River. Northup expresses other arguments against slavery. For instance, Uncle Tom's Cabin focuses on how the legal system prevents even kind owners from treating slaves well and how it releases cruel owners from liabilities for their treatment of slaves.
Such themes appear in Northup's narrative, too. Writing about this work, Eric Herschtal noted that "Slave narratives were never intended to give an unbiased view. They were antislavery polemics meant to bring down the institution." The fact that these works had a purpose was similar to other published works.
Herschtal emphasizes that Northup expressed compassion in his account, quoting him: "It is not the fault of the slaveholder that he is cruel,” Northup writes, “so much as it is the fault of the system under which he lives.” Northup's first-person account of his twelve years of bondage captured attention in the national political debate over slavery that took place in the years leading up to the Civil War. It drew endorsements from major Northern newspapers, anti-slavery organizations, and evangelical groups. It "sold three times as many copies as Frederick Douglass’s slave narrative in its first two years."
Northup's account describes the daily life of slaves at Bayou Boeuf in Louisiana, their diet and living conditions, the relationship between master and slave, and the means that slave catchers used to recapture runaways. His account shares some details similar to those of authors who were escaped slaves, such as Frederick Douglass, Harriet Ann Jacobs, and William Wells Brown. However, Northup was unique in documenting his being kidnapped as a free man from the North and sold into slavery. His perspective was always to compare what he saw to what he knew before while living as a free man in a free state. While there were hundreds of such kidnappings, he was among the few persons who gained freedom again.
Early and mid-twentieth century historians of slavery, Kenneth Stampp, Stanley Elkins, and Ulrich Bonnell Phillips, endorsed the historical accuracy of the book. Eakin and Logsdon in 1968, wrote: "In the last analysis, [the] narrative deserves to be believed, not simply because [Northup] seems to be talking reasonably, not merely because he adorns his tale with compelling and persuasive details. At every point where materials exist for checking his account, it can be verified." These materials include trial records, correspondence, diary, and slave sale records.
While Twelve Years a Slave is the best-known example of someone who was kidnapped and later freed – albeit through extraordinary efforts – historians have begun to research and present other cases. Most of the known court cases of freedom suits related to kidnapping victims were filed in New Orleans, although some were in border states such as Missouri. One such freedom suit took place in Tuscaloosa, Alabama, where Cornelius Sinclair, a free black man from Philadelphia, Pennsylvania, had been sold after being kidnapped in August 1825 and transported South with some younger free blacks. A total of about 20 young blacks disappeared from the Philadelphia area that summer, some survivors sold into slavery in Mississippi. Helped by the intervention of Philadelphia mayor Joseph Watson, most of those kidnapped were returned free to Philadelphia by June 1826, but Sinclair's odyssey was longer. He was freed in 1827 by a unanimous verdict of an all-white jury.
After additional printings in the 19th century, the book went out of print until 1968, when historians Joseph Logsdon and Sue Eakin restored it to prominence. Eakin discovered the story as a child growing up in Louisiana plantation country—the owner of a first edition showed her the book, after finding it in a former plantation home.
Years later, Logsdon had a student from an old Louisiana family who brought a copy of the original 1853 book to class; her family had owned it for more than a century. Together Logsdon and Eakin studied Northup’s account, documenting it through the slave sales records of Washington, D.C. and New Orleans, by retracing his journey and bondage in Bayou Boeuf plantation country in central Louisiana and through its records, and documenting his New York State origins. They found his father’s freeman’s decree, and the case files for the legal work that restored Northup’s freedom and prosecuted his abductors. In 1968, Eakin and Logsdon’s thoroughly annotated edition of the original book was published by Louisiana State University Press, shedding new light on Northup’s account and establishing its historic significance. That book has been widely used by scholars and in classrooms for more than 40 years, and is still in print.
In 1998, Logsdon was invited by scholars in upstate New York to participate in a search for Solomon's grave. However, bad weather prevented the search that year, and Logsdon died the following June 1999. In 2007, shortly before her death at age 90, Eakin completed an updated and expanded version of their book; it includes more than 150 pages of new background material, maps, and photographs. In 2013, e-book and audiobook versions of her final definitive edition were released in her honor. With permission, scholars may use Eakin’s lifetime archives through The Sue Eakin Collection, Louisiana State University at Alexandria, Louisiana. The Joseph Logsdon Archives are available at the University of New Orleans.
Historian Jesse Holland noted in a 2009 interview that he had relied on Northup's memoir and detailed description of Washington in 1841 to identify the location of some slave markets in the capital. Holland has also researched the roles of African-American slaves who, as skilled laborers, helped build some of the important public buildings in Washington, including the Capitol and part of the original Executive Mansion.