Promotion (chess)
In chess, promotion is the replacement of a pawn with a new piece when the pawn is moved to its. The player replaces the pawn immediately with a queen, rook, bishop, or knight of the same. The new piece does not have to be a previously captured piece. Promotion is mandatory when moving to the last rank; the pawn cannot remain as a pawn.
Promotion to a queen is known as queening; promotion to any other piece is known as underpromotion. Promotion is almost always to a queen, as it is the most powerful piece. Underpromotion might be done for various reasons, such as to avoid stalemate or for tactical reasons related to the knight's unique movement pattern. Promotion or the threat of it often decides the result in an endgame.
Rules
When a pawn is promoted, it is removed from the board, and the new piece is placed on the square the pawn moved to. Any piece may be promoted to regardless of whether it has been captured. Consequently, a player might have two or more queens, or three or more rooks, bishops, or knights. In theory, a player could have as many as nine queens, ten knights, ten bishops, or ten rooks, though these are highly improbable scenarios.Representation of promoted pieces
Most chess sets come with only the 32 pieces used in the starting position. Some chess sets come with an extra queen of each color, but this does not accommodate the possibility of having three or more pieces of the same type. When multiple sets are available, promoted pieces are borrowed from other sets if required. Under FIDE rules, a player may stop the clocks and summon the arbiter to provide a piece for promotion.Under US Chess Federation rules and in casual play, an upside-down rook may designate a queen. However, according to FIDE arbiter guidelines, such a move is treated as a legal promotion to a rook.
History
Promotion first existed in chaturanga, an ancestor of chess created in the 6th century. In chaturanga, a pawn is promoted upon reaching the last rank of the board. Historians dispute what the pawn can be promoted to. Some sources state that a pawn can be promoted only to a mantri, an early form of the queen only able to move one square diagonally, with the idea being that a foot soldier that advanced all the way through the enemy lines was promoted to the lowest rank of officer. Others claim that the pawn, if the piece is available for promotion, is promoted to the piece initially positioned on the file on which the pawn stands, except if the pawn stands on the king's file, in which case it is promoted to a mantri. If the piece is unavailable, the pawn remains unpromoted on its square.Chaturanga was introduced to the Middle East as shatranj around the 7th century. In shatranj, a pawn can be promoted only to a fers. As chaturanga and shatranj spread to the western world and eastern Asia, as well as several other regions of the world, the promotion rule evolved.
After the queen gained its modern identity and abilities in the 15th century, replacing the farzin or ferz, some players objected to the fact that a king could have more than one queen via promotion. One old set of chess rules says, "A promoted pawn became a ferz, with the move of the queen."
In Italy, in the 18th and early 19th centuries, a pawn could be promoted only to a captured piece; if none of the promoting player's non-pawn pieces were captured, the pawn remained inactive until a piece became available, whereupon the pawn immediately assumed that piece's role. Philidor did not like the possibility of having two queens; in all editions of his book, he stated that a promotion could only be to a piece previously captured. Lambe also stated this rule in a 1765 book. A player could thus never have more queens, knights, rooks, or bishops on board than the number the player starts with.
The restricted promotion rule was applied inconsistently. Jacob Sarratt's 1828 book gave unrestricted promotion. By Sarratt's time, unrestricted promotion was popular, and according to Davidson, it was universal by the mid-19th century. However, Howard Staunton wrote in The Chess-Player's Handbook, originally published in 1847, that Carl Jaenisch said that the restricted promotion rule was still in force in northern Europe, Russia, Scandinavia, and Germany. For instance, an 1836 Norwegian game-book by Peter Tidemand Malling clearly states "Queen, Rook, or any other officer that has been lost", and this wording was used as late as 1862 for the third and final reprint.
1862 British Chess Association rule
Under Law XIII of the 1862 "Code of Laws of the British Chess Association", a pawn reaching its last rank had the option to remain as a pawn instead of being promoted. In his 1889 work The Modern Chess Instructor, Wilhelm Steinitz, the first World Chess Champion, endorsed this rule, explaining its purpose by referring to the position diagrammed, which he cited from Johann Löwenthal's Book of the London Chess Congress, of 1862.1.Bxg2? loses quickly after 1...Ra1+ 2.Bf1 Rb1, putting White in zugzwang, so the pawn must capture the rook and promote. If White plays 1.bxa8=Q? or promotes to rook, bishop or knight, Black wins with 1...gxh3, whereupon 2...h2 is unstoppable. Instead, White draws by 1.bxa8=P!!, when 1...gxh3 or 1...Kxh3 stalemates White, and other moves allow 2.Bxg2, with a drawn endgame. Steinitz wrote, "We approve of the decision of the London Chess Congress, of 1862, although the 'dummy' pawn rule was denounced by some authorities." The same rule and explanation are given by George H. D. Gossip in The Chess-Player's Manual.
The broad language of Law XIII appears to allow promotion to any piece. This led to the whimsical joke chess problem illustrated. White is to play and checkmate in one move. No solution is possible under modern-day rules, but with Law XIII in effect, the surprising solution is 1.g8=BlackN#!!, when the newly-promoted knight blocks its own king's flight square. Other amusing problems have been created involving promotion to a white or black king, which Law XIII also appears to allow.
Howard Staunton vigorously opposed the 1862 rule when it was proposed, but the tournament committee passed it by a large majority of votes. It did not catch on, however. Philip Sergeant wrote:
A correspondent in the May Chess World... did not exaggerate when he wrote that the B.C.A. Code had been very generally rejected by British amateurs, and emphatically condemned by the leading authorities of America, Germany, and France. In particular, the absurd "dead Pawn" rule, against which Staunton had made his protest in 1862, had failed to win acceptance.
The British Chess Association code was superseded by the "Revised International Chess Code" of the London 1883 international chess tournament, under which promotion is mandatory.
Strategy
The ability to promote is often the critical factor in endgames and thus is an important consideration in opening and middlegame strategy. A far-advanced pawn can threaten to be promoted and thus be a valuable asset. Almost all promotions occur in the endgame, but promotion can happen at any point in the game.Due to the pawn's ability to be promoted, having an extra pawn can often be a decisive advantage. In general, a pawn is more valuable the farther advanced it is, as it is closer to promotion. As a result, it is often beneficial to place a pawn in enemy territory; even if it does not control any important squares, it may still be useful, as it forces the opponent to ensure that it is not promoted.
A passed pawn is a pawn that no enemy pawns can stop from reaching promotion. A passed pawn is highly valuable in the endgame, where few enemy pieces remain to prevent it from being promoted.
A is a situation in which each side tries to promote a passed pawn before their opponent. Usually, the first player to promote wins unless their opponent can promote immediately afterward.
Examples
Opening promotion
Promotion occasionally occurs in the opening, often after one side makes a blunder, as in the Lasker Trap, which features a promotion to a knight on move seven:Schlechter–Perlis, Karlsbad 1911 could have featured a promotion to queen on move 11:
Threatening both 11.cxb8=Q and 11.c8=Q. Perlis avoided the trap with 8...Nxc6!, losing more slowly.
The British grandmaster Joe Gallagher used the same tactical pattern a half-move earlier in Terentiev–Gallagher, Liechtenstein Open 1990:
And now White could have resigned, since if 9.Rxa2,...c2 promotes the c-pawn. In the actual game, White played 9.Nxc3, dropping a rook, and played on in a hopeless position for several more moves.
Another example occurs after the moves:
With the dual threat of 12...hxg1=Q and 12...h1=Q, as in Schuster–Carls, Bremen 1914 and -Torre, Mexico 1928. If 10.Qd2 instead of 10.c3, then 10...exf2+! 11.Kd1 Qxd2+ 12.Kxd2 fxg1=Q rather than 10...Qxe5 11.dxe5 gxh2 12.Nf3 h1=Q 13.0-0-0 with a strong attack.
There are also a few opening lines where each side gets a desperado pawn that goes on a capturing spree, resulting in each side queening a pawn in the opening. An example is seen in P. Short–Daly, 2006 Irish Chess Championship, where play continued 10... bxc3 11. exf6 cxb2 12. fxg7 bxa1=Q 13. gxh8=Q.
Both players promoted by White's seventh move in Casper–Heckert:
More than two queens
In master play, it is rare for one or both players to have more than one queen. One of the best known games in which each side had two queens is Bobby Fischer vs. Tigran Petrosian, 1959 Candidates Tournament, illustrated in the diagram and analyzed extensively in Fischer's My 60 Memorable Games. Four queens existed from move 37 until move 44.Very few games have been played with six queens; two examples are Emil Szalanczy–Nguyen, Thi Mai and David Antón Guijarro–Alejandro Franco Alonso. In the first game, each side had three queens from move 58 to move 65. The game ended in a draw with a single queen on each side. In the second game, both sides also had three queens; Black ultimately resigned with each side having one queen.