no genre of music was ever " invented" by anybody. certainly the monroe group with flatt and scruggs crystallized a sound but it had as much to do with earl's banjo style, chubby wises' non old timey fiddle style and lester's unique rhythm and singing style as it did with bill. i feel certain that at no time did bill monroe wake up screaming "bluegrass!! that's it! i've finally invented bluegrass!" much of the bluegrass standard repertoire was written or co-written by lester flatt and others and many songs credited to bill monroe were in fact written by others and either purchased or co-opted by bill. i am a big fan of monroe and will grant him lots of credit for his contributions but bluegrass music is a product of many influences and to grant monroe all the credit slights other very important contributors i think.