Jean Cocteau

Cocteau wrote poetry, fiction, drama and criticism; he directed several celebrated films; he produced thousands of sketches and paintings; he collaborated with such musicians as Stravinsky, Satie, Milhaud, Poulenc, Honegger, Henze and Menotti; he acted on both stage and screen; he travelled around the world in 80 days (long before S J Perelman, Nicholas Coleridge and Michael Palin); he personally trained the washed-up Panamanian prizefighter Al Brown so effectively that Brown regained his world bantamweight title; and he played the drums in a couple of Parisian nightclubs.
Cocteau reiterated the term "poet" as often and obsessively as a navvy would use another sort of four-letter word, is that he was actually one of the most significant artists of the 20th century. The influence of his writing, both poetry and prose, is detectable in the work of figures as various as Radiguet and Genet, Edith Sitwell and Mishima; that of his film-making in the productions of the New Wave - Truffaut, Godard, Demy, Resnais, Varda and company - as well as in those of Bresson, Melville, Pasolini, Visconti, Bertolucci, Franju, Bergman, Anger, Fassbinder, Ruiz, Carax, Almodovar, Greenaway, Jarman and Tim Burton; and even that of his essential posture in the behavioural mannerisms and sartorial style of countless young French acolytes to this day as equally, if more obliquely, in the white-clown dandyism of someone like Andy Warhol.
In a career that spanned nearly six decades, Cocteau met everybody and did everything (albeit an "everybody" and "everything" as exclusive as they are inclusive). Yet he was also, by virtually universal consensus, a profoundly tormented man - the German novelist and diarist Ernst Junger, who saw a lot of him during the occupation years, referred to him as a "man in hell" but one who "had made himself comfortable there" - and that torment can be traced to two fundamental dramas in his life with which he never properly engaged in his work.
About homosexuality. It was no secret. Yet Cocteau never put his name to an openly, unashamedly homosexual text and invariably alluded to his male lovers - the most celebrated being the precocious novelist Raymond Radiguet and the actor Jean Marais - as his "adopted sons". Even in his private diaries, which he always intended to be published posthumously, he couldn't bring himself to confront the truth of his relationships with them, as though he genuinely hoped to cheat posterity - to cheat God.