As a music city, Cologne gained international significance particularly after World War II. The music of the avant-garde found its most important center here worldwide. Everyone of note could be found in the Rhine metropolis. This trend had already begun in the 19th century with composers such as Johannes Brahms, Giuseppe Verdi, Gustav Mahler, and Richard Strauss. It continued with conductors like Otto Klemperer, Erich Kleiber, Fritz Busch, and numerous singers and instrumental soloists far beyond the city. In recent decades, the boundaries between serious and popular music have increasingly blurred. New names like Wolfgang Niedecken, Höhner, and Bläck Föss have now come to the forefront and quickly gained regional recognition. Cologne, whose citizens may not all be aware of the musical treasures the city now holds, can.