Western opera is a dramatic art form, which arose during the Renaissance in an attempt to revive the classical Greek drama tradition in which both music and theatre where combined. Being strongly intertwined with western classical music, the opera has undergone enormous changes in the past four centuries and it is an important form of theatre until this day. Noteworthy is the huge influence of the German 19th century composer Richard Wagner on the opera tradition. In his view, there was no proper balance between music and theatre in the operas of his time, because the music seemed to be more important than the dramatic aspects in these works. To restore the connection with the traditional Greek drama, he entirely renewed the operatic format, and to emphasize the equally importance of music and drama in these new works, he called them "music dramas".