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Jonathan Eig’s book “King: A Life” is the first comprehensive biography in decades of Martin Luther King Jr., drawing on reams of interviews and newly uncovered archival materials to paint a fuller picture of the civil rights leader than we have received before. “This is a very human, and quite humane, portrait,” our critic Dwight Garner wrote in his review. “Eig’s book is worthy of its subject.”

On this week’s podcast, Eig describes the process of researching and writing the book, and tells the host Gilbert Cruz how he tracked down resources that were unavailable to earlier biographers.

“I was a newspaper reporter for a long, long time — and you know, working on daily stories, if you got five days to work on a story, it was a luxury. Now I’ve got five, six years to work on a story, and I take full advantage of that,” Eig says. “Sometimes it takes me six, eight months just to get the archives to look to see what they’ve got. It took me two years to find, even though I knew it was out there, this unpublished autobiography that Martin Luther King’s father wrote. Nobody had ever quoted from it. I knew it was out there. And the library that had it didn’t know they had it. It took me more than a year just to convince them that they had it, and if they really looked, they could go find it. So stuff like that just gets me really, really pumped up.”

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