Why can't I castle here?

You can't castle "through" check, meaning that you can't castle if the square your king is passing over would be check.

            Sacrifice your knight, or bring your queen to F3, then you can castle.    OR  bring your rook to F1, and castle queen-side later.

Thanks guys, I didn't know about not being able to castle "through" check.

             I think the rule is;  you can't castle into it, throught it, or out of it.

What's embarassing is digging up a post over 4 months old and bagging on a beginner.  Stupid is as stupid does, I guess.  (You probably don't even know where that's from, either.)

You can't call him stupid, he just doesn't know a chess rule.

I'd hate to feel so poorly about myself that I had to dig up threads several months old just to insult people.

Pardon us, mere motals, but even Korchnoi had to ask about castling in his world championship match.

cause the Black Queen horizon cuts the castling-road  of your King