Adolf Hitler
Although not explicitly mentioned, Adolf Hitler looms large over the book. The leader of the Nazi party and the Führer of Germany, Hitler created policies that directly caused the Holocaust, thus imprisoning Frankl and many other Jews and other so-called "undesirables" (and killing 6 million more). If not for Hitler and his goons, then Frankl would not have been imprisoned and would likely not have developed logotherapy, the primary reason for this book's existence.
Viktor Frankl
Author, Pyschiatrist, Neurologist, and Holocaust Survivor wrote Man's Search for Meaning to tell the story of his time in Auschwitz, one of the most infamous and harshest concentration camps during WWII and to provide some context and insight into his theory of logotherapy.
Told through Frankl's point of view, Man's Search for Meaning examines how Frankl and other prisoners survived the horrors of the Holocaust. Through a good attitude and finding meaning, Frankl argued, concentration camp prisoners were more likely to survive. When prisoners give up, he argued, then they were doomed for death.
Tilly Frankl
Again, although Tilly Frankl (Viktor's first wife) does not appear in person in the book, she is an important character nonetheless. Viktor used her to ground himself and to prevent himself from despairing too much by thinking about their love, imagining conversations with her, and by thinking and remembering the time they lovingly spent together before the war. Tragically, she didn't make it out of the camps, but Frankl mentions that she was a major reason why he survived his horrible ordeal.
