When I was younger, my late father told me a story about our surname, a story that, sadly, I haven’t researched further (perhaps admitting this publicly will spur me to do so). Here’s the story: My father was from Cincinnati, which is separated from the small town of Southgate, Ky., by the Ohio River. The Ohio was the last crossing many enslaved people had to make to reach the free northern states. As a child, he heard that a white woman from the Southgate family who founded the town had fallen in love with an enslaved man on her estate. At some point, they married and the man took her surname, not having one of his own.

Many African Americans, whether they know it or not, have a tale something like this in their family history. Usually, the gender roles are reversed, and it is a white man who has had a child with (either by force or by love) a black woman. Many white people also have such stories in their history, though they are sometimes more reluctant to acknowledge it. In any case, because of “the peculiar institution” most African Americans have great difficulty tracing their ancestry much further back than the 1800s. When Henry Louis Gates was able to trace comedian Wanda Sykes’s family back to free blacks in the 1600s, it was a notable rarity. By and large, we were property, counted in with the cows, the pigs and the furniture, with records sketchy if they exist at all.

For obvious reasons, the story of Michelle Obama’s long-dead relatives has also attracted attention. Rachel L. Swarns summed up the facts in a 2009 New York Times article that led to her new book, “American Tapestry”: “[A] union, consummated some two years before the Civil War, represents the origins of a family line that would extend from rural Georgia to Birmingham Alabama to Chicago and finally to the White House. Melvinia Shields, the enslaved and illiterate young girl, and the unknown white man who impregnated her are the great-great-great-grandparents of Michelle Obama, the first lady.”

In “American Tapestry,” Swarns traces both sides of Mrs. Obama’s family back to the 1840s, building carefully to the story of Melvinia Shields. Swarns’s research is extensive and meticulous — one feels the hours that she spent poring over old documents and talking with genealogists and historians. Her passion for the story is clear and striking.

What works against her, and against the full success of the book, is the sketchiness of the history that slavery created and enforced and the rareness of literacy among slaves and their immediate descendants. Very few letters, journals or notes have survived — all the written ephemera so crucial to the historian in discovering the mindset of his or her subjects. Further, many of those in the generations immediately after slavery maintained a staunch silence about the experience, as though to blot out the horror.

Because of that silence, African Americans tend to lack stories from “the old country.” Without these anecdotes and handed-down stories, many of those whom Swarns interviewed have slender and unenlightening memories, as in this quote from Nomenee Robinson, remembering his grandmother Phoebe Robinson, Mrs. Obama’s great-great grandmother on her father’s side: “She was the keeper of wonderful recipes. . . . Rhubarb pie. I’ve never had it since. She made dandelion greens, dandelion soup. That I remember very well.”

We can’t be privy to what was on the minds of Mrs. Obama’s long-dead ancestors as they moved through their challenging lives. Swarns’s effort to create vivid characters and a strong narrative involves a great deal of hypothesizing about what a person might have been thinking or feeling, as here, when she describes Melvinia’s home in Georgia when she was 8: “Blacks and whites often played together as children, and Melvinia may have found some solace in the silly games and childish diversions. She could have closed her eyes and, for a moment, felt just like any other little girl, lost in the joy of play.” Swarns is striving here to imagine the inner lives of the long-dead, but the “could have/might have” formulation, which appears over and over throughout the book, does not create a convincing picture of those inner lives.

Fiction writers are free to state confidently, through imagined characters, how it felt to live through slavery and its horrors (ask Toni Morrison). But the historian is bound by what she can document, or she must give in to conjecture; in this book, that conjecture sometimes seems forced. That said, Swarns has unearthed and disseminated crucial American history here. The journey, over a few hundred years, from house slave to White House is a remarkable, only-in-America story that Swarns tells with care and thoughtfulness.

Swarns also does well with the reaction of some descendants of Mrs. Obama’s white forebear, who, it is revealed in the book’s epilogue, was not her owner, Henry Shields, but his son Charles. Many of those descendants, whatever their political persuasion, do not want to believe that they had an ancestor who was a slave owner (and possibly a rapist). Here’s Swarns quoting Aliene Shields, a distant white relative of Mrs. Obama’s. It’s true that Shields has done substantial genealogical research — but here she is theorizing: “To me it’s an obvious love story that was hard for the South to accept back then. . . . I genuinely think he took care of them. They were his family; there was genuine affection. They were loved.”

Shields has no idea how her ancestor treated Mrs. Obama’s great-great-great grandmother, but her unwillingness to grapple with what is most likely the harsh reality speaks volumes. Swarns chooses to reports this kind of statement (there are others) without embellishment or editorializing. A wise choice. Editiorializing could easily have become hectoring; the fallacy of Shields’s statement is apparent without further comment.

In Mrs. Obama’s DNA is both the best and the worst of America, a narrative and a heritage that we need to know and acknowledge. Whether we like it or not, Swarns forces us to take a hard look at that heritage. For that alone, this book is a worthy and significant endeavor.


Martha Southgate is the author of four novels, most recently “The Taste of Salt.”