I. Basic Description of The Castle Move or Castling.
The King in combination with either of the player's Rooks has an optional move available called the castle move or castling. I use the term "castling" in this tutorial.
The special move involves shielding the King on the back rank (1st rank for White, and 8th rank for Black) away from the center of the chessboard. Most often, this is done behind a three-pawn defensive shield. Castling may be done with less then three pawns for the defensive shield. The defensive power of the pawn shield, however, is reduced when there are less than three pawns forming the shield.
Important to remember is that castling is not only for defense, but also increases the offensive arsenal for a player. Castling accomplishes this by getting one of the player's Rooks away from a wing (a or h file), and onto a square near the center of the board thereby increasing the player's ability to use that Rook during the game.
II. The Mechanics of Castling.
How is Castling Done?The King is moved two squares horizontally either to the right or left side along the back rank, and the Rook toward which the King is moved then is moved to the square in the same rank immediately adjacent to the square upon which the King is placed and toward the center of the chessboard. The King may be castled to either the Kingside or the Queenside. In chess notation, a Kingside castle is noted as 0-0 and a Queenside check is noted as 0-0-0.
Kingside castle: This involves moving the King two squares to the right to the King's Knight square and the King's Rook two squares to the left to the King's Bishop square. The chess notation for a Kingside castle, 0-0, therefore is easily remembered and understandable.
Queenside castle: This involves moving the King two squares to the right to the Queen's Bishop square and the Queen's Rook three squares to the Queen's square. The chess notation for a Queenside castle, 0-0-0, therefore also is easily remembered and understandable.
DIAGRAM: Kingside Castling and Queenside Castling
When Can Castling Be Done? When Can Castling Not Be Done?
Each player may only castle once during a game, and only when:
both the King and Rook to be used in the castling have not moved; and
no opposing piece could check the King either on the square upon which the King would land after castling, or any of the intervening squares between the King and the Rook to be used in the castling. This naturally follows as a corollary, and extension in the case of castling, of the rule that a King may not move to a square upon which the King would be in check; and
the King is not in check (i.e., the King may not castle to get out of check).
Castling cannot be done until at least one pawn advance has occurred and there has been development of two of a player's pieces for a Kingside castle (Bishop and Knight on the Kingside) and three pieces for a Queenside castle (Queen, Bishop, and Knight on the Queenside).
The earliest a Kingside castle may occur is on a player's fourth move.
The earliest a Queenside castle may occur is on a player's fifth move.
Another general guiding principle in chess is to develop Knights first, and then the Bishops: but, for castling a Bishop and a Knight need to be developed. Therefore, castling may occur perhaps out of necessity for King safety before development of both Knights depending on the opening moves made by the players.
III. Reasons for Doing Castling.
Castling provides a defensive shield from the vulnerability of an opponent's central attacks.
Castling frees up the Rook used in the castling toward the center of the chessboard for activity in open files and to be used to provide protection for the player's central pawns.
Castling further usually connects up the two Rooks (unless one has already been lost to the opposing player), greatly enhancing their ability to attack and defend.
International Master Jeremy Silman, in his "Chess Instruction for Beginners, King Safety, Part One", provides the following on castling:
"Why is it important to castle as quickly as possible?
* The center is the most important part of the board (it's FAR more important than the wings). If your opponent opens lines in that area, do you really want your King to take the brunt of his assault?
* If your King is in the middle, your Rooks won't be connected. Playing with one Rook against your opponent's two is very poor math (in other words, castling gets your King to safety AND brings a Rook into play)!
* Why attack when your own King is in the danger zone? It's much better to get his Highness to a safe spot and only then start a battle. NEVER begin a fight if your King isn't safe!
* You can play on if you make a strategic mistake. You can play on if you hang a pawn. But if your King gets mated, the game is over. Simply put: winning a prolonged battle is MUCH easier if your King is safely castled.
* Not castling doesn't necessarily mean you'll be mated. But it will make it harder for your forces to cooperate, and tactics based on the exposed King can easily lead to loss of material."
Let's turn to timing considerations.
IV. Timing - General Considerations.
Castling usually should be done no later than when the opposing player has developed pieces which may attack the King through the center files (d and e files, also called the King and Queen files). A player must also be vigilant that the opposing player is not developing with en eye toward preventing castling. A keen eye on the board position and attention to King safety often will serve you better, especially by players at lower levels of play than a mechanical, rote style of castling as early as possible.
If a player has castled, the opposing player should consider castling as soon as practicable because the opponent has freed up a Rook toward the center area of the chessboard for attacking along open lines, and providing defensive control through open lines, in the center. Therefore, "King safety" dictates getting the opposing King also into a place of maximum protection away from the center of the chessboard as soon as possible. Morphy's Opera Game is a prime example of inadequate attention to King safety and castling for defensive purposes. Morphy took just 17 moves to mate Black in the center of the board, using a withering attack against the defenseless Black King in the center, despite Black still having the Queen on the board.
These are general considerations. Play during the game may dictate on the board that castling not be done, or at least be delayed. Depending on which opening is played, and how the players develop their pieces and pawn structures, ongoing evaluation of game factors is critical. At the same time, do not let castling become an overarching goal. More than one chess player has quickly castled, only to see his defense wilt under a withering attack by the opposing player because of a lack of development and inadequate pawn structure. Experience is the best teacher.
V. To Which Side Should Castling Be Done? General Principles.
Typically, players will castle to the same side of the chessboard, and most often with Kingside castles.
Kingside castles generally provide the most protection for the King because it is ensconced centralized behind three pawns and provides protection for each of them. The King's Knight may be positioned at f3 for White or f6 for Black (each square is said to be the most natural developed square for the King's Knight) constructing a tightly compacted defensive fortress for a usually well-guarded and well-defended King.
Sometimes because of tactics, strategy, and positional reasons, the players will both castle to the Queenside. This is more rare.
In other cases, a player might do a Queenside castle and the opposing player does a Kingside castle, or vice-versa. These are more common than the dual Queenside castles, but less common than the dual Kingside castles.
In a Queenside castle there is a pawn usually left unprotected (the pawn at a2 for White and the pawn at a7 for Black).
The pawns at a2 and a7 in Queenside castles may be attacked and exploited as possible weaknesses in the defense around the shield afforded by castling to the Queenside. This generalized positional weakness provides an avenue into the players' respective seventh and back ranks (for White - the 1st and 2nd ranks: for Black - the 7th and 8th ranks).
The defensive pawns in Queenside castles are not easily defended, and therefore represent a drawback to doing Queenside castles as a normal rule.
A player needs to consider seriously the possible consequences of doing a Queenside castle, as indeed also a Kingside castle. The Queenside castle usually requires the player to do a more thorough and searching examination of the board, material advantage or disadvantage, positional structure, and pawn structure, before deciding to do a Queenside castle, especially if a Kingside castle is still open and available to the player.
However, in some cases, a Kingside castle may no longer be an option. This may be because the King's Rook has been moved, or it is not an option at the time the player wishes to castle because the King is blocked from castling to the Kingside at that point.
For example, castling would be prohibited if an opposing Bishop is attacking and controlling the f1 or g1 squares so that the White King cannot castle to the Kingside; or the f8 or g8 squares so that the Black King cannot castle to the Kingside. Therefore, a Queenside castle might be the only option available.
VI. Is there some way to tell when to castle and not have it be detrimental?
Every player goes through the bad experience of castling, following the above rules and principles, only to see their game plan become shattered, their King becoming very vulnerable, and under an unrelenting attack by the opponent. So, what happened? Isn't castling supposed to be a good thing to do?
As with anything in chess, rules and principles are just...well, plain and simply - general! So...yes, castling generally is a very good thing to do.
The timing of when to do castling, and which type of castling to do, greatly depends on the opening moves which are played by the players. More specifically, when and what type of castling to be done depends on the offensive and defensive structures that have developed or are being developed.
Experimenting with the different types of castling, while developing defensive positions and offensive capabilities around them, should be used as primary guideposts to develop a sense of the timing and to which side you should castle in different situations.
You must gain experience by seeing how "vulnerabilities" in different situations dictate the success or lack of success in castling. The nature of vulnerabilities in different positions, along with the defensive and attacking capabilities on the board that result, will aid you in executing castling to take the fullest advantage of castling's very important defensive power and offensive strengthening capabilities.
Some things a player needs to consider:
* Does the player intend to fianchetto or double finachetto?
* Is either White's or Black's side of the board significantly cramped or limited in space by the pawn structure and/or positioning of pieces on the board, which might dictate or force attacking maneuvers through the other side of the board.
* Is the wing file on the side to which the player intends to castle (the h file for Kingside castles; and the a file for Queenside castles) already opened, or under a threat to be opened, or vulnerable to being opened?
* Can the opposing player obtain a Bishop-Queen or Queen-Bishop battering ram aimed along the diagonal toward the defensive pawn positioned in the wing file?
* Is the King's Knight in a Kingside castle developed to its most natural defensive square...f3 for White Kingside castling and f6 for Black Kingside castling, providing defense for the pawn in the wing file? An open wing file on the side of castling makes a castled King extremely vulnerable for attacking and checkmating.
*When a player has done Kingside castling, the possibility of a back rank mate increases. This is because the three-pawn defensive shield aids in protecting the King from a frontal attack. The opposing player, however, may gain entry to the back rank with a Queen or Rook for a horizontal attack against the castled King, or be able to attack the castled King with a Knight. In such situations, the three-pawn defensive shield may become a significant game-deciding liability. This is because the three pawns block the King's possible flight vertically away from an attack against the castled King. Therefore, a player who has done a Kingside castle must always keep this drawback to castling in mind and keep a keen awareness of an attack against the King while shielded behind the three-pawn defensive shield in front of the castled King.
Let's turn to a defensive and protective manuever available to prevent a back rank mate against a King castled to the Kingside.
VII. Luft: a defensive maneuver to prevent a back rank mate for the King in a Kingside castle.
Luft is advancing one of the pawns in the three-pawn defensive shield to give the King a vertical escape flight square to which the castled King can move if attacked on the back rank by the opposing Queen or Rook, or if attacked by a Knight.
Usually, this is the wing pawn (h-pawn), but may be any of the three pawns. The advance may be either a one square advance (most preferred to keep the minimize decrease in the strength of the three-pawn defensive shield), or a two square advance (will significantly increase the loss of strength for the three-pawn defensive shield).
Important to keep in mind while playing is that doing luft generally begins to breakdown the strength of the three-pawn defensive shield. Therefore, the player will need to ensure (if possible) to keep a strong pawn structure and adequate positional defensive strength with another piece or other pieces to aid in blocking and preventing an attack against the castled King. This has a secondary affect of limiting the mobility of the piece or pieces used to bolster the three-pawn defensive shield.
Below are examples showing luft.
DIAGRAM: Luft with h-pawn (Black)/Luft with g pawn (White)
FEN "3Rr1k1/4Qpp1/p3p2p/8/q7/6P1/4PK1P/8 w - - 0 1"
DIAGRAM: Luft with g-pawn (White)
FEN "6k1/5ppp/4p3/p7/8/qp3QP1/4PP1P/6K1 w - - 0 1"
DIAGRAM: Luft with f-pawn (White)
FEN "3r2k1/1R3ppp/pQ2p3/1b4bN/q7/5P2/4P1PP/6K1 b - - 0 1"
The first and third examples show that luft might not be sufficient to prevent a loss due to other factors such as positional superiority, and the breakdown of the strength of the three-pawn defensive shield. In the first example, with White to move, White's Rook captures Black's Rook, giving White a win due to overwhelming material advantage along with positional superiority despite Black having done luft with the h-pawn to prevent a back rank mate. In the third example, the loss of strength of the three-pawn defensive shield along with a strong position by Black dictates a mate is forth coming against White. 1...Qd1+ 2.Kf2 Bh4+ 3.g3 (3.Ng3 Qxe2+ 4.Kg1 Qe1+ 5.Nf1 Qxf1#) (3.Ke3 Qd2+ 4.Ke4 Bc6+ 5.Qxc6 Qd4#) 3...Qxe2+ 4.Kg1 Rd1#
The foregoing discussion shows that there is a strong connection between King safety and castling early in the game to increase playing strength and mobility on the board. A player needs to keep in mind both the strengths and weaknesses of castling. Doing so allows the player to fend off attacks against his or her King, while being able to develop attacks against the opponent's pieces and pawns. In this aspect, castling should be viewed as an aid both for defensive as well as offensive capabilities for player. I recommend you next review the tutorial The Rook.
