Unknown author · CC BY-SA 3.0 de

Emanuel Lasker held the World Chess Championship for 27 years, the longest reign in the title's history, using a famously psychological style that opponents found difficult to prepare against. He was also a serious mathematician, proving the primary decomposition of ideals in polynomial rings — a result now standard in commutative algebra, taught to students who have never heard of his chess career. Lasker wrote philosophy and drama besides, and invented his own board game, Lasca, late in life.