On this day in 1957, West Side Story opened on Broadway. It has since become a permanent part of American music culture – everybody knows and loves this show and its singing, snapping, dancing gangs. When Leonard Bernstein wrote the music to this show, he had just been appointed music director of the New York Philharmonic. The fact that the conductor of one of the world’s finest orchestras was also writing for music theater showed the depth and breadth of Bernstein’s abilities.