Most historians agree that the game of chess was first played in northern India during the Gupta Empire in the 6th century AD. This early type of chess was known as Chaturanga, a Sanskrit word for the military. The Gupta chess pieces were divided like their military into the infantry, cavalry, elephants, and chariots. In time, these pieces became the pawn, knight, bishop, and rook. The English words chess and check both come from the Persian word shāh meaning king.
The earliest written evidence of chess is found in three romances (epic stories) written in Sassanid Persia around 600AD. The game was known as chatrang or shatranj. When Persia was taken over by Muslims (633–644) the game was spread to all parts of the Muslim world. Muslim traders carried the game to Russia and to Western Europe. By the year 1000 it had spread all over Europe. In the 13th century a Spanish manuscript called Libro de los Juegos describes the games of shatranj (chess), backgammon, and dice.
The game changed greatly between about 1470 to 1495. The rules of the older game were changed in the West so that some of the pieces (queen, bishop) had more scope, development of the pieces was faster, and the game more exciting. The new game formed the basis of modern international chess. Historians of chess consider this as the most important change since the game was invented.