Buñuel was born in northeastern Spain, the eldest of seven children. From his father, Leonardo Buñuel, a businessman, who had left home at the age of 14 to join the army and fight in Cuba in the Spanish-American War (1898), Luis inherited an adventurous spirit. He excelled at school, in Zaragoza, spending only his holidays in his hometown. He was good at sports, such as boxing, and also played the violin well. He attended a Jesuit college in Zaragoza, until at 17 he entered the University of Madrid, where he became a friend of the painter Salvador Dalí (Dalí, Salvador) and the poet Federico García Lorca. In 1920 Buñuel founded the first Spanish movie club and wrote critiques of the films shown there.

Having discovered Freudian psychoanalysis and having broken away from religion, he went to Paris in 1925 and entered film-producing circles, feeling that film would become his true medium of expression. In 1926 he became an assistant director, and in 1928 he directed his first picture, Un Chien andalou (An Andalusian Dog), in collaboration with Dalí. It created a sensation: at a time when movies tended to be dominated by the natural and the literal, Buñuel discovered the cinema of instinct, which issued through him from the Surrealist movement.

His next two films—L'Âge d'or (1930; The Golden Age), a radically anticlerical and antibourgeois film made in France, and Las Hurdes (1932; Land Without Bread), a documentary about a particularly wretched region of Spain—asserted his concern with the freedom to dream and to imagine, his revolutionary attitude toward social problems, his aggressive sense of humour, and his rejection of traditional logic.

In Spain, Buñuel acted as producer of a number of commercial films in an attempt to build a native industry. When the Spanish Civil War began in 1936 he volunteered to the Republican government in Paris, and in 1938, he acted as a technical adviser for two Hollywood films about the Spanish Republic. In the United States, he experienced his greatest difficulties. He did some film editing and worked briefly for the Museum of Modern Art, in New York City, until it became known that he had directed the atheistic L'Âge d'or, and he was allegedly forced to resign. In 1947 he settled in Mexico with his wife and two sons.

There his career was reinvigorated; he directed two pictures designed to have box-office appeal, into which he introduced one or two freely creative sequences. The success of one of these, El gran calavera (1949; The Great Madcap), allowed him to make a personal film, Los olvidados (1950; The Young and the Damned). This fascinating and sympathetic study of slum youths reestablished his reputation as a director of note.

Buñuel exercised more and more freedom in allowing the “free” sequences to invade otherwise conventional films, and his own blasphemous but tender world reappeared more often. Soon all his films, even those imposed upon him by producers, such as Robinson Crusoe (1952), rendered the Buñuelian universe—a dreamland in which strange and unwonted happenings occur. Poetry is combined with an aggressiveness, born of tenderness, in his work. His great films from this Mexican period include Ensayo de un crimen (1955; The Criminal Life of Archibaldo de la Cruz) and Nazarín (1958), about an unworldly priest.

In 1960 Buñuel was allowed to return to Spain to make Viridiana (1961); the Spanish authorities, however, found the completed film to be anticlerical and tried to suppress it. Nonetheless, it was smuggled out to be shown at the Cannes Festival, where it was awarded the top prize. In 1962, in Mexico, he made another major work, El ángel exterminador (The Exterminating Angel), about a formal dinner party from which the guests find themselves powerless to depart; it too was interpreted as having powerful anticlerical connotations.

By then acclaimed throughout the world, Buñuel was again free to make films as he chose, as he had not been since his first period in France. His next film, Le Journal d'une femme de chambre (1964; The Diary of a Chambermaid), was his most overtly political film, wherein the turn-of-the-century story of the decadent French aristocracy is updated and transformed into a metaphor for the growth of Fascism. The 42-minute Simón del desierto (1965; Simon of the Desert), concerning the temptations of anchorite Simeon Stylites, and Belle de jour (1967), about the fantasies of a middle-class woman, though quite different in narrative, explore some of the central themes in Buñuel's work.

His better known, later films—including Tristana (1970), Le Charme discret de la bourgeoisie (1973; The Discreet Charm of the Bourgeoisie), and Cet obscur objet du désir (1977; That Obscure Object of Desire)—also reflect Buñuel's concern with dream and reality, the confusion of true and false, the untrustworthiness of the foundations of social structure, and the nature of obsession itself. His autobiography, My Last Sigh (originally published in French), was published in 1983.

Probably the most controversial of filmmakers, Buñuel owed his fame to his absolute sincerity. Ignoring fashions and conventions, he pursued his career in his native Spain, in France, in the United States, and in Mexico for more than a half century, mostly working within the limitations of the film industry. Yet, no other filmmaker has been more personal, more frank in expressing his own obsessions as evidently in his first film as in his last.