Founder, leader, and chief theoretician of the surrealist movement, the poet André Breton was born in Normandy in 1896. A medical student at the outset of the First World War, Breton served in the army at a neurological ward, where he treated patients for post-traumatic stress, including Jacques Vaché, whose iconoclastic views influenced him considerably. In post-war Paris, Breton sought out writers like Apollinaire and Reverdy, began a periodical Littérature with Philippe Soupault and Louis Aragon, and helped form a French contingent of Dada under the leadership of Tristan Tzara. But already Breton and his friends were moving beyond the absolute negation of Dada to Surrealism, a movement rooted in pure psychic automatism, desire, chance, poetry, and the marvelous. Under Breton's leadership, Surrealism became the most vital European avant-garde of interwar high modernism, its influence extending to Egypt, Japan, and the Caribbean. Exiled to the United States during the Second World War, due to the Nazi occupation, Breton would return to Paris in 1945 and continue to lead the movement until his death in 1966.