Bishop ending

A bishop ending is a position in which bishops are the main pieces left besides the kings and pawns. Each bishop always moves on squares of one color. The first task is therefore to identify whether both bishops travel on the same color or on opposite colors.

Same-colored bishops

When both bishops use the same square color, they can contest the same diagonals, attack the same pawns, and be exchanged for each other. King activity, the creation of a passed pawn, meaning one with no enemy pawns ahead in its vertical column or the neighboring columns, and placing pawns where they do not obstruct their own bishop often determine the result.

Opposite-colored bishops

When one bishop uses only light squares and the other only dark squares, they cannot confront each other directly. A defender may blockade pawns on squares protected by its bishop that the opposing bishop can never attack. These endings therefore have a strong drawing tendency even when one side is a pawn down, but they are not automatic draws. Widely separated passed pawns or several weaknesses may break the blockade.

One basic exception is especially important. A rook pawn is a pawn on an edge column. If that pawn is the only promotion hope, the bishop cannot control its promotion square, and the defending king reaches that corner, king, bishop, and pawn cannot force a win against a lone king. This is the wrong-colored bishop and rook pawn ending.