Peter Gay is a Jewish American historian of the social history of ideas.
Gay’s first interest was in intellectual history. His 1959 book, “Voltaire’s Politics” examined Voltaire as a politician and the how his politics influenced the ideas that Voltaire championed in his writings. Gay followed the success of Voltaire’s Politics with a wider history of the Enlightenment, “The Enlightenment: An Interpretation” (1969), for which he was honored with a National Book prize and the Mecher Book prize.
Gay’s 1968 book, Weimar Culture was considered at the time to be a ground-breaking cultural history of the Weimar Republic. Starting in 1978 with Freud, Jews and Other Germans, an examination of the impact of Freudian ideas on German culture, Gay has become increasingly interested in psychology. Many of his works focus on the social impact of psychoanalysis.
Source-Wikipedia
http://en.wikipedia.org/wiki/Peter_Gay