Double chess is a chess variant invented by Julian S. Grant Hayward in 1916. The game is played on a 16×12 chessboard with each player in control of two complete armies placed side by side.
The rules were published in the January 1929 issue of British Chess Magazine.
The illustration shows the starting setup. A player wins by checkmating either enemy king. Additional rules:
As in standard chess, pawns promote upon reaching the furthest .
J. R. Capablanca, who had experimented with different forms of chess in the 1920s, found the game "remarkably interesting", and a four-game match was held with Géza Maróczy on 22nd to 26th April 1929 at the Royal Automobile Club, Pall Mall, London. Capablanca won the match (20