Stalemate

Stalemate is a situation in the game of chess where the player whose turn it is to move is not in check but has no legal move. The rules of chess provide that when stalemate occurs, the game ends as a draw (i.e. having no winner). During the endgame, stalemate is a resource that can enable the player with the inferior position to draw the game rather than lose. In more complex positions, stalemate is much rarer, usually taking the form of a swindle that succeeds only if the superior side is inattentive. Stalemate is also a common theme in endgame studies and other chess problems.

The outcome of a stalemate was standardized as a draw in the 19th century. Before this standardization, its treatment varied widely, including being deemed a win for the stalemating player, a half-win for that player, or a loss for that player; not being permitted; and resulting in the stalemated player missing a turn. Some regional chess variants have not allowed a player to play a stalemating move. In losing chess, another chess variant, is typically treated as a win for the stalemated player.

In popular usage, the word stalemate refers to a conflict that has reached an impasse, and in which resolution or further action seems highly difficult or unlikely.

With Black to move, Black is stalemated in diagrams 1 to 5. Stalemate is an important factor in the endgame – the endgame set-up in diagram 1, for example, quite frequently is relevant in play (see King and pawn versus king endgame). The position in diagram 1 occurred in an 1898 game between Amos Burn and Harry Pillsbury and also in a 1925 game between Savielly Tartakower and Richard Réti. The same position, except shifted to the e-file, occurred in a 2009 game between Gata Kamsky and Vladimir Kramnik.

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