Sigmund Freud was born in 1856 in Freiberg, Moravia, and moved with his family to Vienna at the age of four, where he would live for almost his entire life. Trained as a neurologist, he described himself in a letter with startling honesty: "I am actually not at all a man of science... I am nothing but a conquistador."
His early research career took a turn that is easy to leave out of the tidy version of his biography: in 1884 he published Über Coca, an enthusiastic paper promoting cocaine as a treatment for depression, fatigue, morphine addiction, and digestive complaints. He used it himself, sent it to his fiancée Martha as a tonic, and recommended it to his close friend Ernst von Fleischl-Marxow — who developed one of the first medically documented cases of cocaine addiction and psychosis as a direct result. It is a genuinely embarrassing chapter, not a footnote to be politely skipped, and Freud's own later silence about it speaks for itself.
His real turn came through Josef Breuer, an older colleague treating a patient known as "Anna O." for hysterical symptoms. Breuer found that simply letting her talk through the origin of each symptom made it disappear — she called it, in English, "the talking cure." Freud built an entire method, then an entire theory of mind, on that single observation.