Many countries claim to have invented the chess game in some incipient form. The most commonly held belief is that chess originated in India, where it was called Chaturanga, which appears to have been invented in the 6th century AD. Although this is commonly believed, it is thought that Persians created a more modern version of the game after the Indians. In fact, the oldest known chess pieces have been found in excavations of ancient Persian territories.
Another theory exists that chess arose from the similar game of Chinese chess, or at least a predecessor thereof, existing in China since the 2nd century BC. Joseph Needham and David Li are two of many scholars who have favored this theory.
Chess eventually spread westward to Europe and eastward as far as Japan, spawning variants as it went. One theory suggests that it migrated from India to Persia, where its terminology was translated into Persian, and its name changed to chatrang. The entrance of chess into Europe, notably, is marked by a massive improvement in the powers of the queen. The oldest known texts describing chess seem to indicate a bi-directional spread from the Persian empire. In fact, the oldest known reference points to Shah Ardashir as being a master of the game, his rule was from 224 - 241 AD. This would indicate that chess was invented some time before his rule.
From Persia it entered the Islamic world, where the names of its pieces largely remained in their Persian forms in early Islamic times. Its name became shatranj, which continued in Spanish as ajedrez and in Greek as zatrikion, but in most of Europe was replaced by versions of the Persian word shah = "king".
There is a theory that this name replacement happened because, before the game of chess came to Europe, merchants coming to Europe brought ornamental chess kings as curiosities and with them their name shah, which Europeans mispronounced in various ways.
* Checkmate: This is the English rendition of shah mat,
which is Persian for "the king is finished".
* Rook: From the Persian rukh, which means "chariot",
but also means "cheek" (part of the face). The piece resembles a
siege tower. It is also believed that it was named after the mythical Persian
bird of great power called the roc. In India, the piece is more popularly
called haathi, which means "elephant".
* Bishop. From the Persian pil means "the elephant",
but in Europe and the western part of the Islamic world people knew little
or nothing about elephants, and the name of the chessman entered Western Europe
as Latin alfinus and similar, a word with no other meaning (in Spanish, for
example, it evolved to the name "alfil"). This word "alfil"
is actually the Arabic for "elephant" hence the Spanish word would
most certainly have been taken from the Islamic provinces of Spain. The English
name "bishop" is a rename inspired by the conventional shape of
the piece. In Russia, the piece is, however, known as "elephant".
In the Indian lingo however, the piece is more popularly known as oont = "camel".
* Queen. Persian farzin = "vizier" became Arabic
firzan, which entered western European languages as forms such as alfferza,
fers, etc but was later replaced by "queen". Incidentally, the Indian
equivalent of "queen", rani is used for the piece by Indians.
The game spread throughout the Islamic world after the Muslim conquest of Persia. Chess eventually reached Russia via Mongolia, where it was played at the beginning of the 7th century. It was introduced into Spain by the Moors in the 10th century, and described in a famous 13th century manuscript covering chess, backgammon, and dice named the Libro de los juegos. Chess also found its way across Siberia into Alaska.
Early on, the pieces in European chess had limited movement; bishops could only move by jumping exactly two spaces diagonally (similar to the elephant in xiangqi), the queen could move only one space diagonally, pawns could not move two spaces on their first move, and there was no castling. By the end of the 15th century, the modern rules for the basic moves had been adopted from Italy: pawns gained the option of moving two squares on their first move and the en passant capture therewith, bishops acquired their modern move, and the queen was made the most powerful piece; consequently modern chess was referred to as "Queen's Chess" or "Mad Queen Chess". The game in Europe since that time has been almost the same as is played today. The current rules were finalized in the early 19th century, except for the exact conditions for a draw.
The most popular piece design, the "Staunton" set, was created by Nathaniel Cook in 1849, endorsed by Howard Staunton, a leading player of the time, and officially adopted by Fédération Internationale des Échecs (FIDE) in 1924.
Chess's international governing body is FIDE, which has presided over the world championship matches for decades. Most countries of the world have a national chess organization as well. Although chess is not an Olympic sport, it has its own Olympiad, held every two years as a team event.