i cannot believe - in a check my opponet just decided to go for rochade, the tower of him was attack

^ lol

strange - but now i know, --> otherwise easy go for me to win this match

Even world championships candidates have had trouble remembering these rules. Victor Kortchnoi had to ask the arbiter during his game against Karpov wether castling was legal.

All Right - thank you for clearing up this really complicate Situation.

When I read „tower“ I know it all.

http://www.chessgames.com/perl/chessgame?gid=1104131
13. 0-0-0+

The beautiful one

@Sarg0n the issue is that in some languages the rook is actually called a 'tower'

#14 "really complicate Situation"

Not at all. This is a short, one sentence rule: castling is forbidden if king moves from/through/into check.

Castling also forbidden if king moves and then returns to e1/e8, regardless of what squares it would traverse/land on