Original: Pieter Cornelis '' Piet '' Mondriaan , after 1912 Mondrian ( , later ; March 7 , 1872 â '' February 1 , 1944 ) , was a Dutch painter .
Simplified: Piet Mondrian ( 7 March 1872 -- 1 February 1944 ) was a Dutch modern artist of the De stijl group .