How do I castle in Chess? Can't get both my King and Castle to move at the same time ;-)

How do I castle in Chess? Can't get both my King and Castle to move at the same time ;-)

any help - much appreciated!

Thanks Iagormax!

Some diagrams to illustrate yorygregovich's point. Each case describes a particular rule of castling, so the overall rules of castling include every of the following examples combined together.

1. King has moved, castling is not permitted permanently for the remainder of the game, regardless of whether the rooks have moved or not

2. One of the rooks has moved but king has not moved, castling is not permitted permanently with the moved rook, but castling is still permitted with the other rook

3. King is in check, castling is not permitted temporarily, unless the king moves out of check, in which case castling is not permitted permanently

4. King passes through an attacked square or lands on an attacked square if castling were to be done. castling is not permitted temporarily

Of course in my above example the Black rook can be captured instead, but what I am trying to illustrate is that the conditions where the king is in check, passes through an attacked square or lands on an attacked square only apply to the king, not the rook. If the rook is attacked, but the king is not obstructed from performing the castling, then castling is still permitted.

Here is another example.

As you can observe, castling is permitted even though the knight attacks the rook (and the queen, obviously).

5. The rook must lie along the same rank as the king. Castling is not permitted with newly promoted e1/e8 rooks.

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Here is an example of all the rules being applied together.

On move 1, Black lands a check on the White king with 1...d2+. By the rules of chess, White is compelled to handle the check. Here, if the White king chooses to move by 2. Kxd2 or 2. Kd1, his/her right to castle has been forfeited for the rest of the game since the White king would have moved. With the alternative move 2. Bxd2, the White king remains not moved yet, so castling is still permitted in the game, although temporarily he would not be able to castle since the squares d1, f1 and g1 are attacked by Black's pieces.

On move 3, White moves his/her a1 rook. As a result, queenside castling is permanently forbidden in the game even if the White rook returns to a1, but this does not affect his eligibility for kingside castling since the White king and the h1 rook have not moved yet, although after 3. Ra3 the squares f1 and g1 are still under attack.

On move 5. Black threatens a check with 5...Re7+. White blocks the check with 6. Be3 to keep alive the possibility of castling. If Black responds with 6...Rxe3+, the White king has no choice but to move to escape the check, in which case the White king will not be able to castle permanently even if the White king returns to e1. Instead, Black plays 6...Re6.

On move 7, White is able to castle kingside since the White king and h1 rook have not moved yet, the king is not in check, the king does not pass an attacked square in the process of castling and the king does not land on an attacked square. The fact that the h1 rook is attacked by the f2 knight is not relevant in considering the castling possibilities here.

To castle in a Chess.com game, simply drag the king to the final castled positions (c1, c8, g1 or g8) and there you are, castling is complete. If the castling does not happen, either one of the rules have not been met or the system does not detect the castling. In the latter case, just try again. DO NOT move the rook to its final castled position. Chess.com treats this as simply an ordinary rook move.

Hope my long post above helps!

yorygregovich & Eric0022 - Thanks very much for explaining all that in such detail - That was REALLY helpful! 

Plus, I didn't realise you couldn't castle whilst in Checkmate  -Thank You! 

No worries, other players visiting this post will understand better thanks to your post. You should thank yourself and praise yourself for allowing new chess players to learn a bit more about castling rules.

In a checkmate, after all, the king would be under check by a piece (just that in this special instance nothing can be done to shrug off the check), so castling would violate at least one of the castling conditiions.