Chess variant

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Chaturanga starting setup.[7] Chaturanga is believed to be the origin of all games in the chess family.

The origins of the chess family of games can be traced to the game of chaturanga during the time of the Gupta Empire in India.[2] Over time, as the game spread geographically, modified versions of the rules became popular in different regions. In Sassanid Persia, a slightly modified form became known as shatranj. Modifications made to this game in Europe resulted in the modern game. Courier chess was a popular variant in medieval Europe, which had a significant impact on the "main" variant's development.[2]

Other games in the chess family, such as shogi (Japan), xiangqi (China), and ouk chatran (Cambodian) are also developments from chaturanga made in other regions. These related games are considered chess variants, though the majority of variants are, expressly, modifications of chess. The basic rules of chess were not standardized until the 19th century, and the history of chess before this involves many variants, with the most popular modifications spreading and eventually forming the modern game.

While some regional variants have historical origins comparable to or even older than chess, the majority of variants are express attempts by individuals or small groups to create new games with chess as a starting point. In most cases the creators are attempting to create new games of interest to chess enthusiasts or a wider audience. Variants normally have the same public domain status as chess, though a few (such as Knightmare Chess) are proprietary, and the materials for play are released as commercial products.

The variations from chess may be done to address a perceived issue with the standard game. For example, Fischer random chess, which randomises the starting positions, was invented by Bobby Fischer to combat what he perceived to be the detrimental dominance of opening preparation in chess.[8] Several variants introduce complications to the standard game, providing an additional challenge for experienced players, for example in Kriegspiel, where players cannot see the pieces of their opponent.

The table below details some, but not all, of the ways in which variants can differ from the orthodox game:

Models for the fairy chess pieces used in Capablanca chess

Variants can themselves be developed into further sub-variants, for example Horde chess is a variation upon Dunsany's Chess.[9]

Some variations are created for the purpose of composing interesting puzzles, rather than being intended for full games. This field of composition is known as fairy chess.

Fairy chess gave rise to the term "fairy chess piece" which is used more broadly across writings about chess variants to describe chess pieces with movement rules other than those of the standard chess pieces. Forms of standardised notation have been devised to systematically describe the movement of these. A distinguishing feature of several chess variants is the presence of one or more fairy pieces. Physical models of common fairy pieces are sold by major chess set suppliers.[10]

Several chess masters have developed variants, such as Chess960 by Bobby Fischer, Capablanca Chess by José Raúl Capablanca, and Seirawan chess by Yasser Seirawan.

Individuals notable for creating multiple chess variants include V. R. Parton (best known for Alice chess), Ralph Betza, Philip M. Cohen and George R. Dekle Sr.

Some board game designers, notable for works across a wider range of board games, have created chess variants. These include Robert Abbott (Baroque chess) and Andy Looney (Martian chess).

While chess, shogi, and xiangqi have professional circuits as well as many organised tournaments for amateurs, play of chess variants is predominately on a casual basis.

A few variants have had significant tournaments. Several Gliński's hexagonal chess tournaments were played at the height of the variant's popularity in the 1970s and 1980s. Chess960 has also been the subject of tournaments, including in 2018 an "unofficial world championship" between reigning World Chess Champion Magnus Carlsen and fellow high-ranking Grandmaster Hikaru Nakamura.[11] Likewise Crazyhouse has seen prize-funded unofficial world championship tournaments with top grandmasters and experts of the game on chess.com and lichess.

Several internet chess servers facilitate live play of popular variants, including Chess.com,[12] Lichess,[13] and the Free Internet Chess Server.[14] The software packages Zillions of Games and Fairy-Max have been programmed to support many chess variants.[15][16]

Some chess engines are also able to play a handful of variants, for instance the version of Stockfish implemented on Lichess is able to play Crazyhouse, King-of-the-hill, Three-check chess, Atomic chess, Horde chess, and Racing Kings.[17] The AI included in Zillions of Games is able to play almost any variant correctly programmed within it to a reasonable standard.[16] Some variants, such as 5D Chess with Multiverse Time Travel, are implausible or even impossible to play physically and exist primarily as video games.

Chess variants have been invented in various fiction.[25] In The Chessmen of Mars author Edgar Rice Burroughs describes Jetan which depicts a war between two races of Martian. An appendix fully defines the rules of the game. More commonly specifics of fictional variants are not detailed in the original works, though several have been codified into playable games by fans. An example of this is Tri-Dimensional Chess from Star Trek. On-screen play was not conducted to any specific rules, but a comprehensive rulebook has been since developed.[2] Another well known example of fictional chess-like game are the Star Wars holochess, or dejarik.[26]

Chess boxing, a hybrid sport of chess and boxing, was depicted in Froid Équateur, a 1992 comic by Enki Bilal and was developed into a real sport in the early 21st century.

Fictional chess variants can involve fantastical or dangerous elements that cannot be implemented in real life. The Chessmen of Mars describes a form of Jetan where the pieces are human beings and captures are replaced by fights to the death between them. The Doctor Who episode "The Wedding of River Song" depicts "Live Chess", which introduces potentially lethal electric currents into the game.

• List of chess variants
• Shogi variant
• Xiangqi variant
• Janggi variant

Wikimedia Commons has media related to Chess variants.

Bibliography

• Cazaux, Jean-Louis; Knowlton, Rick (2017). A World of Chess: Its Development and Variations Through Centuries and Civilizations. McFarland. ISBN 978-0786494279.
• Gollon, John (1968). Chess Variations • Ancient, Regional, and Modern. Charles E. Tuttle Company Inc. LCCN 06811975.
• Pritchard, D. B. (1994). The Encyclopedia of Chess Variants. Games & Puzzles Publications. ISBN 978-0-9524142-0-9.
• Pritchard, D. B. (2000). Popular Chess Variants. Batsford Chess Books. ISBN 978-0-7134-8578-3.
• Pritchard, D. B. (2007). Beasley, John (ed.). The Classified Encyclopedia of Chess Variants (PDF). John Beasley. ISBN 978-0-9555168-0-1.