Hexagonal Chess (1936)

Over the years a number of chess variants have been proposed for boards featuring hexagonally shaped cells (commonly called hexes). The most popular of these is Hexagonal Chess which was invented in 1936 by Wladyslaw Glinski of Poland.

David Pritchard says, in the Encyclopedia of Chess Variants, that Glinski's game is played by over half-a-million people, mostly in Eastern Europe.