The Chinese form of chess is a game as old and rich as the European form of the game. Both games are derived from the Indian game of Chaturanga and both traveled to other lands by trade routes, but there most of the similarity ends.
While the changes to western chess were a matter of slow evolution, experimentation, trial and error, the changes to Siang Ki or Chinese chess were made rapidly and according to legend, with great and pressing incentive. Thus Siang Ki had virtually reached its present form by the eighth century when it was mentioned in the 'Han Kwaihu' (Book of Marvels).
According to legend, when chess first made its appearance in China, the Emperor saw two people playing it. His curiosity piqued, he sent a servant to observe the game, to learn it, and to teach it upon his return. As the game was being explained to him the Emperor became enraged upon learning that the most important piece on the board was called the Rajah, or Emperor. Naturally, mere peasants moving the image of the emperor around to provide entertainment for themselves was intolerable. He did what any absolute ruler whose dignity had been thus abused would he had them beheaded. The emperor also decreed that no game would bear the likeness of any person and that no game would have any piece representing him. As all things are easier with your head attached, these edicts were of course followed, thus leading to some dramatic changes in the way the game was played. These changes follow although not necessarily in the order of occurrence.
First, the board was changed. A river was placed across the center of the board dividing the two sides. Also, the 'fortress' was created, that's the 'X" across what would be the home squares of the king, queen and their pawns in modern chess. (see diagram)
Second, play was moved from the squares to the points between them. This led to the board becoming white with red lines on it (except for the river, which was blue).
Finally, although likely early in the process, the pieces were changed. For obvious health reasons, it was no longer practical to have representational figures. The pieces therefore became black and red discs with characters inscribed upon them.
The use of the king being no healthier than the use of figures, he was replaced by a general (G). The general moves one point vertical or horizontal only and captures as he moves. He cannot leave the fortress. Generals cannot oppose each other on an open file, this constitutes check (even though they can't leave the fortress).
Next, the queen does not exist in Chinese Chess. She has been replaced by two mandarins (M) whose sole purpose in "life" is to protect the General. They move or capture in one point diagonally only and cannot leave the fortress.
Moving out from the center, the next piece is the elephant (E). The elephant moves like the bishop did in early forms of chess. They always move two points diagonally but cannot jump over other pieces. Elephants are not allowed to cross the river. Captures are only at the end of the move, not at the midpoint.
Finally we come to a piece which is familiar, the horse (H) which is almost identical to the chess knight. The horse moves up one point and then diagonal one point. They cannot jump over other pieces but capture them as they move replacing the captured piece. They cannot capture a piece at the midpoint of their move.
At the edge of the board is the chariot (CH). It moves vertically or horizontally any number of open points or until it captures an opposing piece.
The pawns or soldiers (S) move forward one point until they cross the river. After crossing the river, they move forward or horizontally one space. Pawns cannot be 'promoted' to become another piece upon reaching the far side of the board and they can never move backwards; so if they reach the opponent's back they can only move horizontally. Captures are made in the same manner as moves.
The last piece is one which is unique to Chinese Chess. It is the cannon (C). As the pieces represent the branches of medieval armies, the cannon represents the artillery thus providing it with a unique form of attack. The period Chinese artillery was much like the modern mortar, a high-trajectory weapon intended to be fired over friendly troops to strike at the enemy. Thus, while the cannon moves like the chariot, it can only attack an opposing piece if there is another piece, or screen, between the cannon an the piece it is attacking. The screen may be of either color.
In play black always moves first. When capturing all pieces replace the captured piece (occupy the point the captured piece had occupied). A stalemate is a loss for the person who has been stalemated. The general is in check if an opposing piece attacks him or if he is directly opposite the other general with no pieces of either color directly between them.
The following consists of observations on play based upon a very limited number of games and thus should not be confused with expert opinion. As the soldiers have gaps between them before play begins the need to move them to promote the marshalling of forces or development is eliminated. This allows the Siang Ki to get off to a faster start than chess does. Play would seem to revolve around the control of the open files (vertical lines). The defense has certain advantages, particularly the fact that some of the pieces cannot cross the river. This is somewhat offset by the increase in mobility for soldiers when the cross the river. Also the open files at the beginning makes for a very lively game from the outset. Thus it seems that while the defense is more numerous the degree of mobility inherent in the game makes a strictly defensive strategy very risky.
Bell, R.C.,The Boardgame Book. Exeter Books, New York, NY 1983.