Jacques Mieses was a German-born British chess player. He was one of the inaugural recipients of the title International Grandmaster from FIDE in 1950. He became a naturalized British citizen after World War II.p258

Grandmaster (GM) is a title awarded to chess players by the world chess organization FIDE. Apart from World Champion, Grandmaster is the highest title a chess player can attain. Once achieved, the title is held for life, though exceptionally the title can be revoked for cheating.