Shatranj (; ; from Middle Persian chatrang ) is an old form of chess, as played in the Sasanian Empire. Its origins are in the Indian game of chaturaṅga. Modern chess gradually developed from this game, as it was introduced to Europe by contacts in Muslim Al-Andalus (modern Spain) and in Sicily in the 10th century. Etymology and origins The Persian word shatranj ultimately derives from Sanskrit (; ) (catuḥ: "four"; anga: "arm"), referring to the game of the same name: Chaturanga. In Middle Persian the word appears as chatrang, with the 'u' lost due to syncope and the 'a' lost to apocope, such as in the title of the text Mâdayân î chatrang ("Book of Chess") from the 7th century AD. In Persian folk etymology, a Persian text refers to Shah Ardashir I, who ruled from 224 to 241, as a master of the game: "By the help of Providence, Ardeshir became more victorious and warlike than all, on the polo and the riding-ground, at Chatrang and Vine-Artakhshir, and in several other arts." However, Karnamak contains many fables and legends, and this only establishes the popularity of chatrang at the time of its composition. During the reign of the later Sassanid king Khosrau I (531–579), a gift from an Indian king (possibly a Maukhari Dynasty king of Kannauj) included a chess game with sixteen pieces of emerald and sixteen of ruby (green vs. red). The game came with a challenge which was successfully resolved by Khosrau's courtiers. This incident, originally referred to in the Mâdayân î chatrang (c. 620 AD), is also mentioned in Ferdowsi's Shahnama (c. 1010). The rules of chaturanga seen in India today have enormous variation, but all involve four branches (angas) of the army: the horse (knight), the elephant (bishop), the chariot (rook) and the foot soldier (pawn), played on an 8×8 board. Shatranj adapted much of the same rules as chaturanga, and also the basic 16-piece structure. There is also a larger 10×11 board derivative; the 14th-century Tamerlane chess, or shatranj kamil (perfect chess), with a slightly different piece structure. In some later variants the darker squares were engraved. The game spread Westwards after the Islamic conquest of Persia and a considerable body of literature on game tactics and strategy was produced from the 8th century onwards. In early Indian chaturanga ( 500–700), the king could be and this ended the game. Persian shatranj