Watch
Step 1 · A king that stayed home too long
Black to move
r1bqk2r/pppp1ppp/2n5/8/1bBP4/2P2N2/P4PPP/R1BQ1RK1 b kq - 0 9Black is a pawn up and grabs another: 9…Bxc3? 10.Qb3! hits f7 and the bishop. 10…Bxa1 11.Bxf7+ Kf8 12.Bg5: the king can never castle now, the rook on h8 is buried, and White’s pieces arrive first. The safe move was 9…d5, giving the pawn back and getting the king home.
The line: 9…Bb4xc3 10.Qd1-b3 Bc3xa1 11.Bc4xf7 Ke8-f8 12.Bc1-g5
Your move
Step 2 · Get the king home
White to move
r1bqk1nr/pppp1ppp/2n5/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQK2R w KQkq - 4 4Knight and bishop are out on both sides. Before anything opens, put your king where it belongs.
Hint: Your king is still on e1. Get it home before you start anything.
The move: 4.O-O
4.O-O. The king is on g1 behind three pawns and the rook is on f1, ready for the centre. Now you can open lines without worrying about e1.
Also good here
4.c2-c3— Also a main move: preparing d4 (the next lesson). Castle soon after.4.d2-d3— Also a main move: the slow Italian. Castling comes next.4.Nb1-c3— Fine development. Castling should follow within a move or two.
Why not another move?
4.Bc4xf7— …Kxf7. You gave a bishop for a pawn, and Black’s king walks back to safety later. What follows:4…Ke8xf74.Nf3xe5— …Nxe5: a knight for a pawn. The knight on f3 was doing its job; leave it. What follows:4…Nc6xe54.d2-d4— Playable, but …Nxd4 trades your centre pawn off at once and you must spend time regaining it. d4 needs c3 behind it, the next lesson.
Watch
Step 3 · Black hits e4
Black to move
r1bqk1nr/pppp1ppp/2n5/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQ1RK1 b kq - 5 4Black develops and attacks e4. With your king already safe, you can answer calmly.
The reply: 4…Ng8-f6
Your move
Step 4 · Answer calmly
White to move
r1bqk2r/pppp1ppp/2n2n2/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQ1RK1 w kq - 6 5e4 is attacked and your king is home. Guard the pawn with a move that keeps developing.
Hint: e4 is attacked. Guard it with a move that keeps developing.
The move: 5.d2-d3
5.d3. The pawn guards e4 and opens the c1 bishop. King safe, centre solid: a good Italian.
Also good here
5.Rf1-e1— Also good: the rook guards e4 from behind, one of the things castling made possible.5.Nb1-c3— Also fine here, and notice: with your king castled, …Nxe4? no longer works for Black (Nxe4 d5 Nxc5!). The trick needed a target on e1.
Why not another move?
5.c2-c3— …Nxe4! and after d4 d5 Black keeps the pawn. Guard e4 directly first. What follows:5…Nf6xe45.Nf3-g5— …O-O and …d5: the attack on f7 goes nowhere and the knight has to retreat.5.d2-d4— …Bxd4 Nxd4 Nxd4: a trade, and Black has the centre. d4 needs c3 behind it.5.Qd1-e2— Guards e4, but the queen blocks the e-file. Playable, not best.
Decide
Step 5 · Why now?
White to move
r1bqk2r/pppp1ppp/2n2n2/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQ1RK1 w kq - 6 5Same board, one question.
Why castle before the centre opens?
Quick check
- Open files find a king on e1
- Castling wins a tempo
- The rook on f1 attacks f7
Show the correct answer
Correct answer: Open files find a king on e1 — Once the e- and d-files open, a king on e1 is a target, and castling can become impossible: a check, or an attacked square on the path, blocks it. Castle while it is free.
- Castling wins a tempo — Castling does not win a tempo; it spends one. It is worth it because it removes the king from the coming action.
- The rook on f1 attacks f7 — The rook on f1 does not attack f7: the f-pawn is in the way. Its job is the centre, once the e-file opens.
Decide
Step 6 · Gone for good
White to move
r1bq1b1r/ppp3pp/2n1k3/3np3/2B5/5Q2/PPPP1PPP/RNB1K2R w KQ - 2 8Black’s king took on f7 and walked to e6 to hold the knight.
Can Black’s king still castle later in this game?
Quick check
- No, castling is gone
- Yes, once the check is over
- Yes, but only queenside
Show the correct answer
Correct answer: No, castling is gone — No. The king has moved, so castling is gone for the whole game, on both sides. That is the price of a king that leaves home early.
- Yes, once the check is over — No: once the king has moved, castling is lost for the rest of the game, even if it returns to e8.
- Yes, but only queenside — No, on either side. The rule is about the king having moved, not where it stands.
On your own
Step 7 · On your own
White to move
r1bqk2r/ppppbppp/2n2n2/4p3/2B1P3/3P1N2/PPP2PPP/RNBQK2R w KQkq - 1 5Your bishop and knight are out and Black is about to castle. Choose White’s fifth move; look at your king first.
Hint: Your king is on e1 and everything else is ready. What is missing?
The move: 5.O-O
5.O-O. King home, rook on f1. Everything that follows, a4, Nc3, Re1, is easier with the king out of the centre.
Also good here
5.Nb1-c3— Also fine, a developing move; castle next.5.a2-a4— Also good: gaining space on the queenside first is a real plan here. Castle next move.5.Nb1-d2— Also fine: the knight develops; castle next.5.c2-c3— Playable: prepares d4. Castling should follow at once.
Why not another move?
5.Bc4xf7— …Kxf7: a bishop for a pawn. What follows:5…Ke8xf75.Nf3-g5— …O-O, then …Na5 and …d5 chase your pieces: the attack on f7 goes nowhere.5.Qd1-e2— Playable, but the queen blocks the e-file. Castle first.
A quick refresher
In the app this position is not part of the lesson itself: it comes back later, as a review, to check that the idea stuck.
Your move
Your turn as Black
Black to move
r1bqk2r/pppp1ppp/2n2n2/2b1p3/2B1P3/3P1N2/PPP2PPP/RNBQ1RK1 b kq - 2 5White has castled. Your knight and bishop are out. What is your king still doing on e8?
Hint: White has castled. Your king is still on e8.
The move: 5…O-O
5…O-O. Your king is home too. Now both sides can fight for the centre with the kings out of the way.
Also good here
5…d7-d6— Also a main move: it opens the c8 bishop first; castle next.5…h7-h6— Also fine: taking g5 away from the knight and bishop; castle next.5…a7-a6— Fine, a useful retreat square for the bishop; castle next.
Why not another move?
5…Bc5xf2— …Bxf2+?? Rxf2: a bishop for a pawn. The f2 sacrifice needs a follow-up; here there is none. What follows:6.Rf1xf25…Nf6-g4— …Ng4? Ng5! and the knight that moved twice is kicked back: development lost.
What you learned
Castle early: once the king has moved, castling is gone for good, and an open centre finds a king on e1 first.
In your next game
In your next game, castle within the first eight moves unless a concrete threat stops you. Before any capture or push in the centre, check that your king is already home.