Shogi (将棋, “general’s game”) is a Japanese two-player strategy board game which is the most popular chess game in Japan. Like other members of the chess family, shogi shares a common ancestry with Indian chaturanga and Chinese xiangqi.
The origins of shogi are traced to the transmission of early chess forms to East Asia by the first millennium, with evidence for distinct Japanese variants emerging by the Heian period (794–1185). Several large-board and experimental forms were played in medieval Japan, including chu shogi and dai shogi and other expanded variants. The classic rules and strategies of modern shogi were standardized during the Muromachi period (1336–1573) by the four shogi houses, which were officially supported by the shogunate. Over subsequent centuries the game became institutionalized, and in the modern era professional organizations, title systems, and formal ranking structures were established. Today shogi is played by millions in Japan, supported by a developed professional circuit and a substantial body of recorded games and theoretical literature.
Arrival in Japan It is not clear when the ancestral chess-type game that later developed into shogi was brought to Japan. This is in contrast to the game of go, which was almost certainly brought to Japan in or around the Nara period, since a go board is stored in the treasury of . There are tales that relate that it was invented by Yuwen Yong of Northern Zhou, and that brought it back after visiting the country of Tang, but both these tales are likely to have been invented at the start of the Edo period by those keen to make a name for themselves as authorities on shogi.
There are several theories about when shogi spread to Japan, but the earliest plausible date is around the 6th century. It is thought that the pieces used in the shogi of the time were not the current five-sided pieces, but three-dimensional figures, as were used in chaturanga. This parallels the changes in chess pieces, which are more representational and less abstract than those made earlier. However, a large problem with this theory is that as pieces in this form have never been found, let alone stored in the treasury of Shōsōin, there is little physical evidence supporting it.
Another theory gives a later date, stating that shogi was brought to Japan after the start of the Nara period.
The central position of the king (with nine columns), flat pieces with characters on them, and a pawn capturing straight forward resemble Chinese chess (xiangqi), but many other elements of shogi differ from xiangqi.Cazaux and Knowlton, pp. 151–154 For instance, in shogi pieces play on squares rather than intersections, there is a complete pawn line on the third rank, they promote to the piece beside the king (i.e. the gold general) and do so by entering the enemy camp, and the knight can jump. All this differs from Chinese chess, but resembles the games of makruk from Thailand and Cambodia and sittuyin from Myanmar; these also have an elephant which moves in the same way as the silver general. From the Song dynasty through the Ming dynasty, China sent great trade convoys through the southern islands and all around the Indian Ocean and also traded with Japan, so elements of South Asian chess could have reached Japan. Shogi might thus combine strands from Chinese and Southeast Asian chess.
See also the history of chess.
Heian period shogi
One of the oldest documents indicating the existence of shogi is , written by (972 - 1027), a seven-volume work which contains a description of how to write the characters used for shogi pieces, but the most generally accepted opinion is that this section was added by a writer from a later generation. Nonetheless, it gives a revealing detail that the pieces had two characters inscribed on them, rather than one character as in xiangqi. (1058–1064), written by Fujiwara Akihira also has passages relating to shogi, and is regarded as the earliest document on the subject.
The oldest archaeological evidence is a group of 16 shogi pieces excavated from the grounds of Kōfuku-ji in Nara Prefecture, and as a wooden writing plaque written on in the sixth year of Tengi (1058) was found at the same time, the pieces are thought to be of the same period. The pieces of the time appear to have been simple ones made by cutting a writing plaque and writing directly on the surface, but they have the same five-sided shape as modern pieces. The pieces found were three kings, four golds, one silver, one knight, and five pawns. As "Shin Saru Gakuki", mentioned above, is of the same period, this find is backed up by documentary evidence. Four more were found in 2013, a few feet away from the original sixteen, and of the same period: they were another knight, another pawn, an unreadable piece, and interestingly a drunk elephant (blank on the other side, so that it did not promote).
The dictionary of common folk culture, , which it is estimated was created between 1210 and 1221, a collection based on the two works and , thought to have been written by , describes two forms of shogi, large (dai) shogi and small (shō) shogi. So as not to confuse these with later types of shogi, in modern times these are called Heian shogi (or Heian small shogi) and Heian dai shogi. Heian shogi is the version on which modern shogi is based, but it is written that one wins if one's opponent is reduced to a single king, apparently indicating that at the time there was no concept of pieces in the hand. However, the board size and number of pieces was not stated, so it is unknown if Heian shogi was already played on the modern 9×9 board or not. Heian great shogi was played on a 13×13 board.
The pieces used in these variants of shogi consist of those used in Heian shogi: the king, gold general, silver general, knight, lance, and pawn, and those used only in Heian great shogi: the copper general, iron general, side mover, tiger, flying dragon, free chariot and go between. The pieces of Heian shogi have their modern moves, promoting to gold when they reach the enemy three lines. According to Kōji Shimizu, chief researcher at the Archaeological Institute of Kashihara, Nara Prefecture, the names of the Heian shogi pieces keep those of chaturanga (general, elephant, horse, chariot and soldier), and add to them the five treasures of Buddhism (jewel, gold, silver, katsura tree, and incense). There is also a theory by Yoshinori Kimura that while chaturanga was from the start a game simulating war, and thus pieces were discarded once captured, Heian shogi involved pieces kept in the hand.
Medieval shogi
In the 14th century, the Fustu Shodoshu (a compilation by the monk Ryoki) mentions a sho shogi (small shogi) and a dai shogi (large shogi). However, only a few pieces are mentioned. For the first time, the rook is mentioned, but only in dai shogi – so that this dai shogi is not the same as the one detailed in the Nichureki. Also mentioned are the lance, reverse chariot, go-between, angry boar, and knight, which agrees with later descriptions.Cazaux and Knowlton, pp. 161–162 The game of dai shogi appears to have been much played and enjoyed in the 14th century, when it probably reached a form similar to that described in the 1443 Shogi Shushu no Zu: 65 pieces per side on a 15×15 board. (The 1443 Shogi Shushu no Zu is lost, but Minase Kanenari's 1591 book Shogi Zu states that he had copied the 1443 book, and that the 1443 book itself was a copy of an older book of which no information survives.)Cazaux and Knowlton, pp. 176–177 Soon, however, its rules were simplified (removing the weakest pieces) to produce the game of chu shogi (middle shogi), first mentioned in the mid-14th century Yugaku orai (along with dai shogi). This is played with 46 pieces per side on a 12×12 board. At some point in the 15th century, three pieces from chu shogi were added to sho shogi: the rook, bishop, and drunk elephant. This meant that sho shogi now differed from the modern form only in the presence of the drunk elephant and the absence of drops. The drunk elephant promotes to a crown prince, which acts as a second king that must be captured as well as the first one to win.
A trio of shogi games – small, middle, and large – continued to be the norm in the 15th century. Chu shogi was the most popular and held in the highest esteem, and sho shogi regarded as trivial, until the introduction of drops in the latter. Dai shogi seems to have been seen as too complicated. (Indeed, the version of dai shogi that comes down to us may not be the original, but may be a late one including influence from chu shogi. In Heian shogi, sho shogi, modern shogi, and Heian dai shogi, weak stepping pieces promote to gold; but in chu shogi, they promote to other pieces in the initial setup that cannot be obtained through promotion, like rooks and bishops. In dai shogi, the pieces available in chu shogi promote as in that game, but the remaining pieces all promote to gold. This suggests that dai shogi originally had all the weak pieces promote to gold, and that promotions from chu shogi were copied back into dai shogi when chu shogi had eclipsed dai shogi in popularity.)Dai Shogi at The Chess Variant Pages
It is thought that the rules of modern shogi were fixed in the 16th century, when the drunken elephant was removed from the set of pieces, and drops were introduced. This may have been inspired by mercenaries switching allegiances, and by the pentagonal shape of shogi pieces pointing towards their opponent. (The drunk elephant still exists in a sho shogi set from 1567, but not in the diary of Matsudaira Ietada in 1587. It may have been removed because its promotion to crown prince does not work well in a game with drops.) According to , a set of shogi rules published in 1696, during the Genroku period, it states that the drunken elephant piece was removed from the game of sho shogi by Emperor Go-Nara during the Tenmon period (1532–1555), but whether or not this is true is not clear.
As many as 174 shogi pieces have been excavated from the Ichijōdani Asakura Family Historic Ruins, which are thought to be from the latter half of the 16th century. Most of these pieces are pawns, but there is also one drunken elephant, leading to the hypothesis that in this period variations of shogi with and without the drunken elephant existed side by side.
The rules of standard modern shogi were first codified in the 1636 treatise Shogi Zushiki by the second Meijin Ohashi Soko. A full description of chu shogi appears in the 1663 Chu Shogi Zushiki of the third Meijin Ito Sokan.
When drops were added, the tables were turned on chu shogi; standard shogi became ascendant. Nonetheless, chu shogi continues to be played by some Japanese players even now, and its exotic pieces (including the drunk elephant and the lion, which essentially moves like a king twice per turn, thus making it able to capture twice) attract interest from all around the world.
Other variants
Minase Kanenari's 1591 book Shogi Zu was itself copied as the 1811 book Shogi Rokushu no Zushiki of Tsurumine Shigenobu. Both the Shogi Zu and Shogi Rokushu no Zushiki state that they were changed once. The book contains six games: the aforementioned trio of sho, chu, and dai shogi, as well as three larger games. They are dai dai shogi (96 pieces per side on a 17×17 board), maka dai dai shogi (96 pieces per side on a 19×19 board), and tai shogi (177 pieces per side on a 25×25 board). The descriptions of these three games are signed by Minase, so they were probably invented between 1443 and 1591 and modified from the original text.