Much of the world that Wilkerson diligently recalls reflects the frustrations and limitations of what James Baldwin pessimistically called "the anguished Diaspora." As the poet and thinker E. Ethelbert Miller has observed, "Diaspora" no longer fits a people who have access to powerful technology that can reverse their dispersal. But the recombinant blackness that Miller celebrates was in evidence even as the descendants of slaves set out for what they hoped were friendlier climes.

They may not have had the Internet, but they had ways of getting the word out, and the most efficient was the Chicago Defender. Distributed secretly by Pullman porters -- "the midwives of the Great Migration," in Wilkerson's memorable phrase -- the paper painted a picture of mesmerizing possibilities. That picture helped draw blacks to cities in unfathomable numbers. "Beginning in World War I, as many as seven thousand people were estimated to be living in a single block in Harlem," Wilkerson reports. By the '70s, when the migration was finally winding down, "nearly half of all black Americans -- some forty-seven percent -- would be living outside the South, compared to ten percent when the Migration began."

To be sure, there was no shortage of the anguish that Baldwin lamented, and Wilkerson doesn't flinch from exposing it. The journeys of Foster, Starling and Gladney are fraught with hurdles that Wilkerson often re-creates with impressive skill. By 1997, for example, Gladney's South Chicago neighborhood had become split between earnest, hardworking people and drug-dealing criminals, "both co-existing on the same streets, one at odds with the other." But just as plentiful, and perhaps more resonant, are examples of the migrants' triumphant spirits, the unshakable willingness to believe in a way out of no way.

Perhaps it's fitting, then, that Wilkerson's tone at book's end is mostly valedictory. Her three central figures, she writes, "believed with all that was in them that they were better off for having made the Migration, that they may have made many mistakes in their lives, but leaving the South had not been one of them."

She notes with some sadness, "Many years later, people would forget about the quiet successes of everyday people" like Gladney and her fellow strivers. Wilkerson is wrong, of course, and it's a good thing. Her steady, careful work here will bring Ida Mae and company a hard-earned portion of immortality. 

Jabari Asim's latest book is A Taste of Honey: Stories. His grandparents relocated north from Liberty, Miss., during the Great Migration.

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