Master biographer Rosemary Sullivan was praised for her exhaustive knowledge and the sense of humanity that permeates her latest book, Stalin’s Daughter: The Extraordinary and  Tumultuous Life of Svetlana Alliluyeva (HarperCollins Canada). Sullivan  conducted this interview on Oct. 6, the evening she won the Hilary Weston Writers’ Trust Prize for Non-fiction.

What initially drew you to Svetlana Alliluyeva? When Svetlana died in 2011 I read in the obituaries that she was quoted as saying, “No matter where I go, to an island or Australia, I’ll always be the political prisoner of my father’s name.” It wasn’t just that she was a  prisoner, but this idea that she was a political prisoner. She also said something like, “You can’t regret your fate, but I do regret that my mother didn’t marry a carpenter.” She had wit.

How challenging was the research? It was massive. I have never exhausted my brain so much. But it was exciting because it involved interviews with 40 people, including a CIA agent who invited me to stay at his house; Stalin’s grandson; Svetlana’s cousins in Moscow; and her colleagues. But there’s always this balance between the interviews, which you then have to transcribe, and the research.

What were you surprised to learn about Svetlana? She was difficult and often in a rage. But everyone had something to say about her life. What moved me was her stamina and will, which kept her going. She had optimism that made no sense given the tragedy she had been through. Svetlana lived to 85 years old. What would it be like to live that long under the name of one of the world’s most brutal dictators and never be able to escape it?