Rook (chess)

White rook
Black rook

A rook (/ɹʊk/; ♖,♜) is a piece in the strategy board game of chess. Formerly the piece was called the tower, marquess, rector, and comes (Sunnucks 1970). The term castle is considered informal, incorrect, or old-fashioned.[1][2] However, in Persian the word for "castling" is qal'eh raften (from qal'eh, "castle") and not rokh raftan.

Each player starts the game with two rooks, one on each of the corner squares on their own side of the board.


Initial placement and movement

The white rooks start on squares a1 and h1, while the black rooks start on a8 and h8. The rook moves horizontally or vertically, through any number of unoccupied squares (see diagram). As with captures by other pieces, the rook captures by occupying the square on which the enemy piece sits. The rook also participates, with the king, in a special move called castling.

Permitted rook moves
abcdefgh
8
a8 black rook
h8 black rook
a1 white rook
h1 white rook
8
77
66
55
44
33
22
11
abcdefgh
Starting positions of the rooks
abcdefgh
8
d8 white circle
g8 black circle
d7 white circle
e7 white pawn
f7 black circle
g7 black rook
h7 black circle
d6 white circle
g6 black circle
d5 white circle
g5 black pawn
a4 white circle
b4 white circle
c4 white circle
d4 white rook
e4 white circle
f4 white circle
g4 white circle
h4 white circle
d3 white circle
d2 white circle
d1 white circle
8
77
66
55
44
33
22
11
abcdefgh
The white rook can move to any square marked with a white dot. The black rook can move to squares with a black dot, or it can capture the white pawn on e7.

History

Illustration of a siege tower, which the rook may be intended to represent.

In the medieval shatranj, the rook symbolized a chariot. The Persian word rukh means chariot (Davidson 1949:10), and the corresponding pieces in the original Indian version chaturanga have ratha (meaning "chariot"), while east Asian chess games such as xiangqi and shogi have names also meaning chariot (車).[3]

Persian war chariots were heavily armoured, carrying a driver and at least one ranged-weapon bearer, such as an archer. The sides of the chariot were built to resemble fortified stone work, giving the impression of small, mobile buildings, causing terror on the battlefield. However, in the West the rook is almost universally represented as a crenellated turret. One possible explanation is that when the game was imported to Italy, the Persian rukh became the Italian word rocca, meaning fortress, and from there spread in the rest of Europe. Another possible explanation is that rooks represent siege towers the piece is called torre, meaning tower, in Italian, Portuguese, and Spanish; tour in French; toren in Dutch; Turm in German; and torn in Swedish. In Hungarian it is bástya ("bastion"). Another possibility is that, as chess moved to Europe long after chariot warfare had been abandoned, a different symbol was needed to represent the rook's concept of feudal power (the chariot being a method of warfare only used by the elite, very similar to medieval knights), and as such the Europeans adopted a castle to represent a lord and his feudal power, further supported by the (albeit later) name for the rook, the "marquess", named after a nobleperson. Finally, the chariot was sometimes represented as a silhouette, a square with two points above representing the horse's heads, which may have been seen to resemble a building with arrowports to the medieval imagination. An exception is seen in the British Museum's collection of the medieval Lewis chess pieces in which the rooks appear as stern warders or wild-eyed Berserker warriors. Rooks usually are similar in appearance to small castles, and as a result a rook is sometimes called a "castle" (Hooper & Whyld 1992). This usage was common in the past ("The Rook, or Castle, is next in power to the Queen" Howard Staunton, 1847) but today it is rarely if ever used in chess literature or among players, except in the expression "castling".[4]

In some languages the rook is called a ship: Thai เรือ (reūa), Armenian Նավակ (navak), Russian ладья (ladya).

In Bulgarian it is called the cannon (Топ, Romanised top).

In Kannada it is known as ಆನೆ (āāne), meaning "elephant". This is unusual, as the term "elephant" is in many other languages applied to the bishop (in Kannada, the bishop is ಒಂಟೆ (ōnté), "camel".

Strategy

Relative value

In general, rooks are stronger than bishops or knights (which are called minor pieces) and are considered greater in value than either of those pieces by nearly two pawns but less valuable than two minor pieces by approximately a pawn. Two rooks are generally considered to be worth slightly more than a queen (see chess piece relative value). Winning a rook for a bishop or knight is referred to as winning the exchange. Rooks and queens are called heavy pieces or major pieces, as opposed to bishops and knights, the minor pieces.

Placement

In the opening, the rooks are blocked in by other pieces and cannot immediately participate in the game; so it is usually desirable to connect one's rooks on the first rank by clearing all pieces except the king and rooks from the first rank and then castling. In that position, the rooks support each other, and can more easily move to occupy and control the most favorable files.

A common strategic goal is to place a rook on the first rank of an open file (i.e. one unobstructed by pawns of either player), or a half-open file (i.e., one unobstructed by friendly pawns). From this position, the rook is relatively unexposed to risk but can exert control on every square on the file. If one file is particularly important, a player might advance one rook on it, then position the other rook behind doubling the rooks.

A rook on the seventh rank (the opponent's second rank) is typically very powerful, as it threatens the opponent's unadvanced pawns and hems in the enemy king. A rook on the seventh rank is often considered sufficient compensation for a pawn (Fine & Benko 2003:586). In the diagrammed position from a game between Lev Polugaevsky and Larry Evans,[5] the rook on the seventh rank enables White to draw, despite being a pawn down (Griffiths 1992:102–3).

Two rooks on the seventh rank are often enough to force victory, or at least a draw by perpetual check.[6]

Polugaevsky vs. Evans, 1970
One white rook on the 7th rank
abcdefgh
8
g8 black king
b7 black pawn
d7 white rook
g7 black pawn
a6 black pawn
c6 black pawn
a5 white pawn
f5 black pawn
b4 black rook
e3 white pawn
f2 white king
g2 white pawn
h2 white pawn
8
77
66
55
44
33
22
11
abcdefgh
White to move, draws
Chigorin vs. Steinitz, Havana 1892
Two connected black rooks on the 7th rank
abcdefgh
8
a7 black pawn
b7 black pawn
e7 white rook
h7 black pawn
e6 white knight
f6 black king
g6 black bishop
d5 white pawn
f5 black pawn
b4 white bishop
h4 black pawn
a2 white pawn
b2 white pawn
d2 black rook
e2 black rook
h2 white pawn
f1 white rook
h1 white king
8
77
66
55
44
33
22
11
abcdefgh
Black to move, 32...Rxh2+ and White resigns, seeing that 33.Kg1 Rdg2#

Endgame

Rooks are most powerful towards the end of a game (i.e., the endgame), when they can move unobstructed by pawns and control large numbers of squares. They are somewhat clumsy at restraining enemy pawns from advancing towards promotion, unless they can occupy the file behind the advancing pawn. As well, a rook best supports a friendly pawn towards promotion from behind it on the same file (see Tarrasch rule).

In a position with a rook and one or two minor pieces versus two rooks, generally in addition to pawns, and possibly other pieces – Lev Alburt advises that the player with the single rook should avoid exchanging the rook for one of his opponent's rooks (Alburt 2009:44).

The rook is a very powerful piece to deliver checkmate. Below are a few examples of rook checkmates that are easy to force.

abcdefgh
8
b8 white rook
g8 black king
d7 white rook
e2 white king
8
77
66
55
44
33
22
11
abcdefgh
A two-rook checkmate
abcdefgh
8
b8 white rook
g8 black king
g6 white king
8
77
66
55
44
33
22
11
abcdefgh
A king and rook mate. The king and rook work together to force the enemy king to the edge of the board, where it can be checkmated.
abcdefgh
8
g8 black king
f7 black pawn
g7 black pawn
h7 black pawn
g5 white rook
f2 white pawn
g2 white pawn
h2 white pawn
b1 black rook
g1 white king
8
77
66
55
44
33
22
11
abcdefgh

Heraldry

Arms of the English family of Rookwood, featuring chess rooks as a cant on the name

Chess rooks frequently occur as heraldic charges. Heraldic rooks are usually shown as they looked in medieval chess-sets, with the usual battlements replaced by two outward-curving horns. They occur in arms from around the 13th century onwards.

In Canadian heraldry, the chess rook is the cadency mark of a fifth daughter.

Unicode

Unicode defines two codepoints for rook:

U+2656 White Chess Rook (HTML ♖)

U+265C Black Chess Rook (HTML ♜)

See also

Notes

  1. Oxford English Dictionary 2nd ed. (online version, accessed Jan. 27, 2009), entry for "Castle", def. 9. "Chess. One of the pieces, made to represent a castle; also called a ROOK.". New Oxford American Dictionary, 2nd ed. (2005) says that "castle" is informal and an "old-fashioned term for rook". The Oxford Companion to Chess, by David Hooper & Kenneth Whyld, 2nd ed. (1992), p. 344 says "In English-speaking countries non-players sometimes call it a castle...". Let's Play Chess by Bruce Pandolfini (1986) p. 30, says "The rook is the piece mistakenly called the castle."; The Everything Chess Basics Book by Peter Kurzdorfer and the United States Chess Federation, Adams Media 2003, page 30, says "... often incorrectly referred to as a castle by the uninitiated".
  2. The Official Rules of Chess by Eric Schiller, The US Chess Federation Official Rules of Chess (five editions by various authors), Official Chess Handbook, by Kenneth Harkness, Official Chess Rulebook by Harkness, and The Official Laws of Chess by FIDE (two editions) all use only the term "rook". Books for beginners such as Bobby Fischer Teaches Chess, A World Champion's Guide to Chess by Susan Polgar, The Complete Book of Chess by I. A. Horowitz & P. L. Rothenberg, and Chess Fundamentals by José Capablanca (2006 revision by Nick de Firmian) also only mention "rook".
  3. 現代漢語詞典 ISBN 978-962-07-0211-2
  4. Lasker 1947, p. 8: "The name 'Castle' is rarely if ever used in modern chess literature for this piece." Horton 1959, p. 175: "Sometimes the Rook has been called a "Castle" but in modern chess literature this term is rarely, if ever, used."
  5. Polugaevsky vs. Evans
  6. The two rooks are sometimes colloquially referred to as "pigs on the seventh", because they often threaten to "eat" the opponent's pieces or pawns.

References

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