French composer Olivier Messiaen (1908-1992). His musical language is derived from a number of varied sources, including Greek metrical rhytms, Hindu tradition, birdsong and catholicism. Messiaen became organist at the church of la Trinité in Paris, a position he held until his death.
Messiaen found birdsong fascinating; he believed birds to be the greatest musicians and considered himself as much an ornithologist as a composer. He notated birdsongs worldwide, and he incorporated birdsong transcriptions into a majority of his music. His innovative use of colour, his personal conception of the relationship between time and music, his use of birdsong, and his intent to express profound religious ideas, all combine to make it almost impossible to mistake a composition by Messiaen for the work of any other western composer.