Simplify the following text for a Grade 6 native English-speaking person.
Original: Karl Ernst Adolf Anderssen ( Breslau , 6 July 1818 â `` Breslau , 13 March 1879 ) was a German chess master , and a teacher of mathematics .
Simplified: Karl Ernst Adolf Anderssen ( July 6 , 1818 â `` March 13 , 1879 ) was a German chess master .