Complex sentence: John Heartfield (born Helmut Herzfeld; 19 June 1891--26 April 1968) was an artist and a pioneer in the use of art as a political weapon.
Split into simpler sentences: John Heartfield (born Helmut Herzfeld; 19 June 1891--26 April 1968) was an artist. He was a pioneer in the use of art as a political weapon.