Final answer:
Sigmund Freud's major influences in the development of psychoanalytic theory were French neurologist Jean-Martin Charcot and his older colleague Josef Breuer. While Carl Jung and Alfred Adler are often associated with Freud, they were his followers, not his influences.
Step-by-step explanation:
Sigmund Freud was a highly influential figure in the history of psychology, offering the first comprehensive theory of personality, which emphasized the role of the unconscious mind and the importance of early childhood experiences. Freud's influences primarily came from his own time period, with significant figures being Jean-Martin Charcot and Josef Breuer. Charcot was a French neurologist whose work on hypnosis greatly influenced Freud's thinking about the unconscious mind. Breuer, Freud's older colleague and friend, worked with Freud on the famous case of Anna O. and contributed to the development of his psychoanalytic theory. While Freud later collaborated with Carl Jung and Alfred Adler, they were not his influences; instead, they were followers who branched off to develop their own psychological theories, often referred to as neo-Freudians, who modified Freud's ideas to create new theories about personality.