Simplify the following text for a Grade 8 native English-speaking person.
Original: Joseph Willem Mengelberg ( 28 March 1871 â `` 21 March 1951 ) was a Dutch conductor , famous for his performances of Mahler and Strauss with the Concertgebouw Orchestra .
Simplified: Willem Mengelberg ( born Utrecht , 28 March 1871 ; died Zuort , Switzerland , 22 March 1951 ) was a Dutch conductor .