Walter Charles Langer (February 5, 1899 – July 4, 1981) was a psychoanalyst from Cambridge, Massachusetts who prepared a psychological analysis of Adolf Hitler in 1943 for the Office of Strategic Services (OSS), that predicted his suicide as the "most plausible outcome" among several possibilities identified. Well before the assassination attempt in the summer of 1944, Langer's report also identified the possibility of a military coup against Hitler. The report is available online and, along with collateral material including a foreword, introduction and afterword, was published in 1972 by Basic Books as The Mind of Adolf Hitler.
Langer was born on February 5, 1899 in South Boston to Charles Rudolph and Johanna Rockenbach, recent immigrants from Germany. His mother was born to a Lutheran household in Zweibrücken, Germany, and his father was a member of the Moravian Brethren from Silesia, Germany. His older brother William became the history department chair at Harvard University, and took a leave of absence during World War II to serve as head of the Research and Analysis section of the Office of Strategic Services. Walter Langer, who for a time was also a professor at Harvard, held a Ph.D but not an M.D. and was the first person admitted to the American Psychiatric Association who lacked a medical degree.