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Checkmate (frequently shortened to mate) is a situation in chess (and in other boardgames of the chaturanga family) in which one player's king is under attack and there is no way to meet that threat; it is a check from which there is no escape. The king is never actually captured — the game ends as soon as the king is checkmated. A player who is checkmated loses the game. Delivering checkmate is the ultimate goal in chess (although not all games end in checkmate — most often a player resigns before checkmate is administered, or the game may end in a draw in several ways).
If a king is under attack but the threat can be met (by capturing the checking piece, moving the king to an unattacked square, or interposing a piece between the king and the checking piece unless the checking piece is a knight), then the king is said to be in check, but is not in checkmate. If a player is not in check but has no legal move (that is, no valid move that would not put the king in check), the result of the game is stalemate, and the game ends in a draw. (See Rules of chess.)
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Origin of the word
The term checkmate is an alteration or Hobson-Jobson of the Persian phrase "Shah Mat" which means, literally, "the King is ambushed" (or "helpless" or "defeated"). It does not literally mean "the King is dead", although that is a common misconception.
Moghadam traced the etymology of the word mate. It comes from a Persian word mandan, meaning "to remain", which is cognate with the Latin word manco. It means "remained" in the sense of "abandoned" and the formal translation is "surprised", in the military sense of "ambushed" (not in the sense of "astonished"). So the king is in mate when he is ambushed, at a loss, or abandoned to his fate.
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Basic checkmates
Here are the common fundamental checkmates when one side has only his king and the other side has only the minimum material needed to force checkmate, i.e. (1) one queen, (2) one rook, (3) two bishops on opposite colors, or (4) a bishop and a knight. The king must help in accomplishing all of these checkmates. If the superior side has more material, checkmates are easier. For instance, two rooks, a queen and a rook, or two queens can easily force checkmate without the help of their king. The process is to put the two pieces on adjacent ranks or files and gradually force the king to the side of the board, where one piece checks the king and the other keeps the king on the edge of the board .
The checkmate with the queen is the most important, but it is also very easy to achieve. It often occurs after a pawn has queened. The next most important one is the checkmate with the rook, and it is also very easy to achieve. The checkmates with the two bishops and with a bishop and knight are not nearly as important, since they only occur infrequently. The two bishop checkmate is fairly easy to accomplish, but the bishop and knight checkmate is difficult and requires precision.
Two knights cannot force checkmate against a lone king. However, under some circumstances, two knights and a king can force checkmate against a king and pawn (or rarely pawns). The winning plan, quite difficult to execute in practice, is to blockade the enemy pawn(s) with one of the knights, maneuver the enemy king into a stalemated position, then bring the other knight over to checkmate. Three knights and a king can force checkmate against a lone king, and four knights can do so even without their king's participation. Those situations, which require one or more promoted knights, are almost never seen outside of chess problems.
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Queen
These diagrams show representatives of the basic checkmate positions with a queen, which can occur on any edge of the board. Naturally, the exact position can vary from the diagram. With white to move, checkmate can be forced in at most ten moves from any starting position, with optimal play by both sides . In the first position, the queen is directly in front of the opposing king. In the second position, the kings are in opposition and the queen mates on the rank of the king. See for a demonstration of how the king and queen versus king mate is achieved.
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Rook
This diagram shows the basic checkmate position with a rook, which can occur on any edge of the board. With white to move, checkmate can be forced in at most sixteen moves from any starting position . The second diagram shows a slightly different position where the kings are not in opposition but the defending king must be in a corner. Again, see for a demonstration of how the king and rook versus king mate is achieved.
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Two bishops
Here are the two basic checkmate positions with two bishops (on opposite colors), which can occur in any corner. (Two bishops on the same color cannot checkmate.) The first is a checkmate in the corner. The second one is a checkmate in a side square next to the corner square. With the side with the bishops to move, checkmate can be forced in at most nineteen moves .
It is not too difficult for two bishops to force checkmate, with the aid of their king. Two principles apply:
The bishops are best when they are near the center of the board and on adjacent diagonals. This cuts off the opposing king.
The king must be used aggressively, in conjunction with the bishops.
In the third diagram, White wins by first forcing the black king to the side of the board, then to a corner, and then checkmates. It can be any side of the board and any corner. In algebraic notation, the process is:
1. Ke2 Ke4 (Black tries to keep his king near the center)
2. Be3 (forcing the king back, which is done often)
5. Ke4 Kd6 (Black tries a different approach to stay near the center)
6. Bc4 (White has a fine position. The bishops are centralized and the king is active.
6... Kc6 (Black avoids going toward the side)
7. Ke5 Kd7 (Black is trying to avoid the a8 corner)
8. Bd5 (keeping the black king off c6)
10. Bd6! (an important move that forces the king to the edge of the board)
10... Ke8 (Black is still avoiding the corner)
11. Ke6 (now the black king can't get off the edge of the board)
12. Bc6 (forcing the king toward the corner)
12... Kc8 (Black's king is confined to c8 and d8. The white king must cover a7 and b7)
15. Kb6 Kd8 (Now White must allow the king to move into the corner)
17. Be7! (an important move that forces the king toward the corner)
18. Bd7! (the same principle as the previous move)
19. Bd8 (White must make a move that gives up a tempo. This move is one, along with Bc5, Bf8, Be6, or Ka6.)
21. Bc6, as in the first diagram in this section .
Note that this is not the shortest forced checkmate from this position. Müller and Lamprecht give a fifteen move solution, however it contains an inaccurate move by Black (according to endgame tablebases) . With optimal play by both sides, checkmate in this position requires seventeen moves. The longer variation is more instructive.
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Bishop and knight
This checkmate is the most difficult to force, because these two pieces cannot form a linear barrier to the enemy king from a distance. Also, the checkmate can be forced only in a corner which the bishop controls.
Here are the two basic checkmate positions with a bishop and a knight, or the bishop and knight checkmate. The first position is a checkmate by the bishop, with the king in the corner. The second position is a checkmate by the knight, with the king in a side square next to the corner. Alternatively, the knight can be on c6 or d7 in the second position.
With white to move, checkmate can be forced in at most thirty-three moves from any starting position , except those in which the black king is initially forking the bishop and knight and it is not possible to defend both. However, the mating process requires accurate play, since a few errors could result in a draw either by the fifty move rule or stalemate.
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Two knights
It is impossible for the stronger player to force checkmate with two knights. In the diagram, if Black plays 1... Ka8? (see algebraic chess notation), White can checkmate with 2. Nbc7, but Black can play 1... Kc8 and escape the threat. The defender's task is easy — he simply has to avoid moving into a position in which he can be checkmated on the next move, and he always has another move available in such situations .
In the diagram on the right, White can play 1. Nc6+ Ka8, but now if White plays 2. Nb5 threatening 3. Nc7, Black is stalemated. It is sometimes possible to force checkmate with two knights against a pawn, because in some positions, having a pawn removes this stalemate defence.
Three knights and a king can force checkmate against a lone king. Four knights can force checkmate against a lone king even without their own king's participation. These situations are generally only seen in chess problems, since one or more of the knights must be a promoted piece, and there is very rarely a reason (e.g., avoidance of stalemate) to promote a pawn to anything other than a queen (see underpromotion).
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Rare checkmate positions
In some rare positions it is possible to force checkmate with a king and bishop versus a king and pawn or a king and knight versus a king and pawn.
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Stammas mate
In the diagram showing Stamma's mate, White to move wins :
White also wins if Black is to move first:
This checkmate has occurred in actual games, see Nogueiras-Gongora, which proceeded
82. Nc5 Ka2 (if 82... a2 then 83. Nb3
83. Nd3 (reaching the first position)
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Unusual checkmate positions
There are also positions in which a king and knight or bishop can checkmate a king and bishop, but checkmate can't be forced (see the diagrams for some examples). Nevertheless, it keeps these material combinations from being ruled a draw because of "insufficient mating material" or "impossibility of checkmate".
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Quick checkmates
The fastest possible checkmate from the initial position is in two moves. This occurs in fool's mate when White moves the king's bishop's pawn one or two squares and king's knight's pawn two squares, and Black's queen is moved to the king's rook's file (1.f3 e5 2.g4 Qh4 in algebraic notation). The fastest possible checkmate by White is in three moves, administered either by the queen or bishop on h5 or g6, e.g. 1.e4 g5 2.d4 f6 3.Qh5 or 1.e3 f6 2.Bd3 h6 3.Bg6, (the fastest possible mate by a bishop) or by the queen on e5 (1.e4 e5 2.Qh5 Ke7 3.Qxe5). The fastest possible mate by a knight is on Black's third move, e.g. 1.e4 Nc6 2.c3 Ne5 3.Ne2 Nd3. The fastest possible mate by a rook is on White's fifth move, e.g. 1.h4 g5 2.hxg5 Bh6 3.Rxh6 Nf6 4.Rxh7 Ne4 5.Rxh8 or 1.a4 b6 2.a5 Bb7 3.a6 Qc8 4.axb7 and 5.bxc8(R) (this, or 5.bxc8(Q), is also the fastest possible mate by a promoted pawn).
Some common or notable mating patterns have names of their own. Apart from the aforementioned fool's mate, these include scholar's mate, smothered mate, the back rank mate, Boden's mate, epaulette mate, and Légal's mate (see below).
Some opening traps involve an early checkmate. These include:
Benoni Defense 1.d4 c5 2.d5 e6 3.Nc3 exd5?! 4.Nxd5 Ne7 5.Bg5 h6 6.Bh4 Qa5+ 7.c3 Nf5?? 8.Qa4!! Qxa4 9.Nc7
Budapest Defense 1.d4 Nf6 2.c4 e5 3.dxe5 Ng4 4.Bf4 Nc6 5.Nf3 Bb4+ 6.Nbd2 Qe7 7.a3 Ngxe5! 8.axb4?? Nd3
Caro-Kann Defense (from above) 5.Bc4 Ngf6 6.Ng5 e6 7.Qe2 Nb6 8.Bd3 h6 9.N5f3 c5 10.dxc5 Nbd7!? 11.b4 b6 12.Nd4! bxc5?? 13.Nc6! Qc7 14.Qxe6+! (1-0 Perenyi-Eperjesi, Budapest 1974) fxe6 15.Bg6
Caro-Kann Defense 1.e4 c6 2.Nc3 d5 3.Nf3 dxe4 4.Nxe4 Bf5?! 5.Ng3 Bg6? 6.h4 h6 7.Ne5 Bh7 8.Qh5! g6 9.Bc4! e6 10.Qe2 Nf6?? 11.Nxf7! Kxf7 12.Qxe6+ (1-0 Alekhine-Bruce, Plymouth 1938) Kg7 13.Qf7
Caro-Kann Defense 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nf6 5.Qd3!? e5?! 6.dxe5 Qa5+ 7.Bd2 Qxe5 8.0-0-0! Nxe4?? 9.Qd8+!! Kxd8 10. Bg5++ (Réti-Tartakower, Vienna 1910) 10...Ke8 11.Rd8
Dutch Defense 1.d4 f5 2.Bg5 h6 3.Bh4 g5 4.Bg3 f4? 5.e3 h5 (5...fxg3?? 6.Qh5) 6.Bd3!? Rh6?? 7.Qxh5+! Rxh5 8.Bg6
Dutch Defense 1.d4 f5 2.h3 Nf6 3.g4 fxg4 4.hxg4 Nxg4 5.Qd3 Nf6?? 6.Rxh7! Rxh7 7.Qg6
Englund Gambit 1.d4 e5?! 2.dxe5 Nc6 3.Nf3 Qe7 4.Bf4 Qb4+ 5.Bd2 Qxb2 6.Bc3?? Bb4 7.Qd2 Bxc3 8.Qxc3 Qc1
From Gambit 1.f4 e5 2.fxe5 d6 3.exd6 Bxd6 4.Nf3 (4.b3?? Qh4+ 5.g3 Qxg3+ 6.hxg3 Bxg3 Pantelidakis-Rhine, Chicago 1974) g5 5.h3?? Bg3 Napetschnig-Rhine, Chicago 1977
Grünfeld Defense 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.e4 Nxc3 6.bxc3 Bg7 7.Bc4 c5 8.Ne2 cxd4 9.cxd4 Nc6 10.Be3 Qa5+!? 11.Bd2 Qa3 12.Rb1 0-0 13.d5? Ne5 14.Bb4? Qf3!! 15.gxf3?? Nxf3+ 16.Kf1 Bh3
Marshall Defense 1.d4 d5 2.c4 Nf6?! 3.cxd5 Nxd5 4.Nf3 Nc6? 5.e4 Nf6 6.Nc3 Bg4 7.d5 Ne5? 8.Nxe5! Bxd1 9.Bb5+ c6 10.dxc6 Qc7?? 11.cxb7+ Kd8 (after 11...Qd7 and 11...Nd7, White mates, or forces mate, with 12.bxa8(Q) or bxa8(R)) 12.Nxf7
Nimzowitsch Defense 1.e4 Nc6 2.d4 d5 3.exd5 Qxd5 4.Nf3 Bg4 5.Nc3 Bxf3 6.Nxd5 Bxd1 7.Nxc7+ Kd8 8.Nxa8 Bxc2 9.Bf4 Nxd4 10.Nc7? e5! 11.Bxe5?? Bb4. Also possible is 7...Kd7 8.Nxa8 Bxc2 9.Bf4 e5 10.dxe5 Bb4+ 11.Ke2 Nge7 12.e6+ fxe6 13.Nc7?? Nd4+ 14.Ke3 Nef5
Owen's Defense 1.e4 b6 2.d4 Bb7 3.Bd3 f5?! 4.exf5! Bxg2 5.Qh5+ g6 6.fxg6! Nf6?? 7.gxh7+! Nxh5 8.Bg6
Philidor's Defense 1.e4 e5 2.Nf3 d6 3.Bc4 Bg4?! 4.Nc3 g6? 5.Nxe5! Bxd1?? 6.Bxf7+ Ke7 7.Nd5 Légal-Saint Brie, Paris 1750. This mating pattern is now called Légal's mate.
Robatsch Defense 1.e4 g6 2.Nf3 d6 3.Bc4 Nd7?? 4.Bxf7+! Kxf7 5.Ng5+ Kf6 (otherwise 6.Ne6 wins the queen) 6.Qf3+ Kxg5 (6...Ke5 7.Qc3+ Kf4 8.Qg3
Ruy Lopez 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.0-0 Nxe4 6.d4 exd4?! 7.Re1 d5 8.Nxd4 Bd6 9.Nxc6 Bxh2+! 10.Kh1! Qh4 11.Rxe4+! dxe4 12.Qd8+! Qxd8 13.Nxd8+ Kxd8 14.Kxh2 f5?? 15.Bg5 http://www.chessgames.com/perl/chessgame?gid=1380684 Pandolfini-NN, 1970
Scandinavian Defense 1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5 4.d4 c6 5.Nf3 Bg4 6.Bf4 e6 7.h3 Bxf3 8.Qxf3 Bb4 9.Be2 Nd7 10.a3 O-O-O?? 11.axb4!! Qxa1+ 12.Kd2! Qxh1 13.Qxc6+! bxc6 14.Ba6
Sicilian Defense 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Qc7 7.0-0 Nf6 8.Qe2 Ng4! 9.h3?? Nd4! (winning White's queen, at least) 10.Nxd4? Qh2
Sicilian Defense 1.e4 c5 2.d4 cxd4 3.c3 d5 4.exd5 Qxd5 5.Nf3?! Bg4 6.Qa4+ Nc6 7.Nxd4 Bd7 8.Nb5? 0-0-0! 9.Nxa7+?? Nxa7 10.Qxa7 Qd1+!! (0-1 Dutch-Sugden, London 1964) 11.Kxd1 Bg4+ 12.Kc2 Bd1 or 12.Ke1 Rd1 (an ending strikingly similar to Réti-Tartakower, Vienna 1910, cited above)
Sicilian Defense 1.e4 c5 2.Nf3 Nf6 3.e5 Nd5 4.Nc3 e6 5.Nxd5 exd5 6.d4 Nc6 7.dxc5 Bxc5 8.Qxd5 Qb6 9.Bc4 Bxf2+ 10.Ke2 O-O 11.Rf1 Bc5 12.Ng5 Nd4+ 13.Kd1 Ne6 14.Ne4 d6 15.exd6 Bxd6?? 16.Nxd6 Rd8 17.Bf4! Nxf4? 18.Qxf7+ Kh8 19.Qg8+! (1-0 Unzicker-Sarapu, Siegen Olympiad 1970) Rxg8 20.Nf7
Sicilian Defense 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 b5 8.e5 dxe5 9.fxe5 Qc7 10.Qe2 Nfd7 11.0-0-0 Bb7 12.Qg4 Qxe5 13.Bd3 Nf6? 14.Bxf6 Qxf6? 15.Rhe1 h5 16.Nxe6! Be7 (16...hxg4 17.Bxb5+! Ke7 (17...axb5? 18.Nc7 or 18.Nxg7) 18.Nxf8+ Kxf8? 19.Re8) 17.Bxb5+! axb5 18.Nc7+! Kf8 19.Rd8+! Bxd8 20.Re8
Three Knights Game 1.e4 e5 2.Nf3 Nc6 3.Nc3 g6 4.d4 cxd4 5.Nd5 Bg7 6.Bg5 Nge7? 7.Nxd4! Bxd4?? 8.Qxd4! Nxd4 9.Nf6+ Kf8 10.Bh6
Vienna Game 1.e4 e5 2.Nc3 Nf6 3.Bc4 Nxe4 4.Bxf7+ (4.Nxe4 d5) Kxf7 5.Nxe4 Nc6 6.Qf3+ Kg8?? 7.Ng5! Qxg5 8.Qd5
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See also
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Notes
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