Why is there a cross on the king piece in chess?

Answer 1

The pieces in Chess all represent opposing kingdoms as would have been involved in wars of the distant past. The rooks (chariots), knights, bishops, and pawns represent the allied forces within a realm. In some early forms of chess, the queen was actually a weak piece with the same movement as the king. Later changes in the rules of movement made her the most powerful of the pieces.

The queen can move in the same manner as do rooks and bishops. This makes her powerful in attacks. But like all the other pieces, she is still used to protect the king.

Answer 2

It is a representation of a Crown .