 Sullivan wrote most of his twenty part songs prior to the beginning of his long collaboration with W. S. Gilbert.Chorley had also collaborated with Sullivan on other songs, on Sullivan's first (but never-produced) opera, "The Sapphire Necklace" (completed in 1867), and on a piece for chorus and orchestra, "The Masque at Kenilworth" (Birmingham Festival, 1864).With the growth of choral societies during the Victorian era, part songs became popular in Britain (as they had earlier in Germany and elsewhere).