(CBS Local)– Eleanor Roosevelt was the nation’s longest-serving First Lady of the United States, but there is so much more to her story than just that. Author David Michaelis dives into the many fascinating layers of Roosevelt’s personal and professional life in his new biography for Simon & Schuster called “Eleanor.”

Michaelis’ single volume biography covers six decades of Roosevelt’s life and documents her maturation on topics like women’s rights and human rights and also shines a light on the complexities of the former First Lady’s marriage to President Franklin Roosevelt. The author hopes readers can see a different side of Roosevelt than they’ve seen before.

Former American First Lady and diplomat Eleanor Roosevelt (1884 – 1962) smiles while boarding a plane, wearing a fur coat, early 1950s. (Photo by Hulton Archive/Getty Images)

“I felt strongly as I began the book that I wanted to convey to people not the Eleanor they thought they knew, we all sort of think we know who she was, but the Eleanor who she was in the context of her life,” said Michaelis, in an interview with CBS Local’s DJ Sixsmith. “And the trouble with biographies about most figures like Eleanor is they’re stretched over three volumes. There are really strong biographies of her husband Franklin that do a really strong job with her. I felt like what we are missing as a culture was to understand Eleanor whole. See her life whole and see how she made the great transformation that we know she made, but how does she do it. In 19 months, her entire family with the exception of herself and her youngest brother were orphaned and they went to live with their grandmother. That began this saga for her of who she thought she would be and being held back again and again and again for the next 15 or 20 years. Eleanor Roosevelt’s life doesn’t really begin until she was 35 or 40.”

Michaelis himself actually met Roosevelt as a kid when he was four years old and his mother was producing the former First Lady’s television show later in her life. The author said he struggled writing this book because the men he had written about previously in Charles Schultz and painter N.C. Wyeth had fairly simple lives by comparison to Roosevelt. The challenge of writing this book and succinctly encapsulating Roosevelt’s story is what made this project so interesting to Michaelis.

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“Eleanor just kept opening up and up and her life kept opening outward,” said Michaelis. “As her life kept opening outward, so did the things she cared about and things she was trying to make changes in and be useful to. Causes, civil rights, human rights. I kept thinking in my writing that I would be able to resolve these. That she would resolve them and her own life would resolve the questions that were raised in each of these areas. It really didn’t it and it wasn’t until I finally realized that it was simply by getting up every day and continuing to try that she made sense of her own life. She spoke candidly to people about doing one thing every day that you’re afraid to do.”

“Eleanor” is available now wherever books are sold and watch all of DJ Sixsmith’s interviews from “The Sit-Down” series here.