Caïssa originated in a 658-line poem called Scacchia Ludus published in 1527 by Hieronymus Vida, which describes in Latin Virgilian hexameters a chess game between Apollo and Mercury in the presence of the other gods. In it, to avoid unclassical words such as rochus or alfinus, the rooks are described as towers on elephants' backs, and the bishops as archers: A leaked unauthorized 742-line draft version was published in 1525. Its text is very different, and in it Caïssa is called Scacchia, the chess rook is a cyclops, and the chess bishop is a centaurarcher. This led to the modern name "castle" for the chess rook, and thus the term "castling", and the modern shape of the European rook chesspiece. Also for a time, some chess players in Europe called the rook "elephant" and the bishop "archer". In German, Schütze became a general word for a chess bishop until displaced by Läufer in the 18th century.
William Jones's poem
The young English orientalist William Jones re-used the idea of a chess poem in 1763, in his own poem Caïssa or The Game at Chess written in English heroic couplets. In his poem, Caïssa initially repels the advances of the god of war, Mars. Spurned, Mars seeks the aid of the god Euphron, brother of Venus, who creates the game of chess as a gift for Mars to win Caïssa's favor. It is an unproven assumption that Jones's name "Caïssa" is an equivalent to Vida's name "Scacchia". The English version of Philidor's 1777 Systematic introduction to the game and the analysis of chess contained Jones's poem. In 1851 the poem was translated into French by Camille Théodore Frédéric Alliey.
Modern use
Caïssa is referred to in chess commentary.
Garry Kasparov uses this reference now and again, especially in his five-volume work My Great Predecessors. It is used as a substitute for being fortunate – "Caïssa was with me" – especially in unclear situations, for example in sacrifices.
The 1994 book The March of Chess Ideas by Anthony Saidy extensively uses Caïssa as well.
T. R. Dawson extensively used Caïssa, both as a character to provide literary narrative to accompany his problem collections, or merely as a convenient anthropomorphism of chess.
The chess variant Caïssa Britannia, created by Fergus Duniho, was named after Caïssa.
When writing about chess, Heinrich Fraenkel used "Assiac" - which is "Caïssa" spelled backwards - as a pseudonym.
