Courier chess

Courier chess (or courier game, from the German: Läufer-spiel) is a chess variant that dates probably from the 12th century and was popular for at least 600 years. It was a part of the slow evolution towards modern chess from medieval chess.

Courier chess is named after one of its most powerful pieces, the courier or runner (läufer), which moves like the modern bishop. This was a unique move at the time of the game's introduction.