The game of chess has a particularly long and fascinating history of more than 1500 years. Over the centuries, there have also been hundreds of different chess variants, all of which incorporate the fundamental distinguishing feature of standard chess: the explicit individuation of different types of pieces with different values and movements to be jointly manipulated by each player towards the overarching objective of cornering the opponent's king.

Some of these games – such as Xiangqi, Shogi, Janggi, and Makruk – are still very popular throughout many parts of the world (particularly Asia), while others – such as courier chess or Tamarlane's Chess – are now typically only played by games specialists. But all testify to the remarkable degree of diversity that the game of "chess" has spawned over the centuries, providing tangible evidence of how the games we play are often a significant reflection of our societal values.

Historians agree that chess originated in northern India somewhere during or shortly before the 5th century CE. Played on an uncheckered 8x8 board called an ashtāpada, it was clearly created as a simulation of war, with its very name, chaturanga (literally "four-limbed") being a standard Sanskrit term of reference for the ancient Indian army composed of four components: foot soldiers, elephants, cavalry and chariots. To the pieces representing each of these four forces, they added the king and his minister, with the object of the game to capture the opponent's king.

Very few explicit early Indian literary references to the game exist, with the generally recognized starting point coming from a passage in the Harshachārita, or Deeds of Harsha – a biography of the north Indian king Harsha Vardhana written by the celebrated Sanskrit poet Bānabhatta, who spent many years at his court.

Harsha's kingdom was known far and wide to be a haven of tolerance, prosperity, and good governance, and his court attracted many leading artists and writers, such as Bana, together with many foreign travelers, including the 7th-century Chinese scholar Xuanzang. In his glowing tribute of the singularly peaceful climate of Harsha's realm, Bana invokes a series of vivid metaphors, such as "Only bees (shatpada) quarrel in collecting dews (dues)" before revealingly concluding with "Only ashtāpadas teach the position of the chaturanga…" (Murray, 60).

This was the first known invocation of chess as a substitute, if not training, for actual war.

From India, the game chaturanga spread westwards into the Sassanian Empire (224 to 651), becoming the Persian chatrang. Several Middle Persian texts explicitly cite chatrang as one of the key skills that an upper-class Sassanian nobleman would possess as part of their general training and education.

But the most revealing chess-related literary reference of all from that era is the fable, On The Explanation of Chess and Backgammon, in which the great Sasanian king of kings, Kosrau I (reign 531 to 579), is approached by an Indian king who challenges him to a sort of intellectual duel. The Indian king shows him 32 priceless emerald and ruby pieces and tells him that if he is smart and wise enough, Kosrau should be able to figure out the rules of chatrang. If he does, the Indian king will duly pay tribute, but if he fails, Kosrau will pay instead.

The Persians are initially at sea until the king's wisest advisor enters the fray and saves the day, triumphantly declaring that he will not only deduce the rules of this new game but will also invent an additional game that the Indians will not be able to solve.

He promptly deciphers the rules of chatrang before resoundingly beating the Indians three times in a row at it (this is a Persian story, after all). And then he presents them with the new game of backgammon – which the Persians call "nard" after Ardashir I (180 to 242), the founder of the Sassanian dynasty – and the Indians are completely stymied.

From this key Middle Persian text, we know the names, at least, of the different pieces of ancient Sassanian chatrang:

Unfortunately, we know nothing specific about how the pieces move or the actual rules of the game. But however those ancient Persians played chatrang, their language has become forever embedded in the game, with the Persian cry "shah mat" – the king is helpless – eventually turning into our modern "checkmate".

With the Arab conquest of the Sassanian Empire in the mid-7th century, chess rapidly passed into the Islamic world. Now called shatranj, most of the pieces developed Arabicized versions of their Persian names.

As the popularity of chess increased steadily throughout the Umayyad Caliphate (661 to 750), the shapes of the pieces gradually transformed from individual figural carvings to a more standardized abstract type sometime around the 8th century, likely a sign of an increasing demand for ready-made shatranj sets.

When the Umayyads gave way to the Abbasid Caliphate in 750, the popularity of chess increased even further. The Arabic literature of the time is filled with tales of early expert players – several of whom played blindfolded – but it is in the 9th and 10th centuries that the game really came into its own, with famous stories of legendary chess masters such as al-Adli, ar-Razi, and al-Suli – all of whom wrote books on chess that were continuously recopied for centuries.

From these manuscripts, we know both the movement of the pieces and the basic rules of play. But those early chess books did much more than just spell out the rules of shatranj. They were filled with ingenious chess problems, known as mansubat, to help the willing student master the many tactical and strategic complexities of shatranj.

It is widely believed that chess penetrated Europe at various points of direct intersection between the Islamic and Christian worlds, primarily Italy and Spain, no later than the early 10th century – and possibly considerably earlier still – whereupon it quickly spread far and wide.

As the game entered Europe, the form of the pieces started to change as well, moving from abstract back to figural, with occasional exquisite instances of innovatively combining the two. With the creation of the so-called Charlemagne chessmen in southern Italy in the latter part of the 11th century, the figural forms are back with a vengeance: the queen is now well established, but the old-fashioned chariot and elephant are still very much present. As queens, kings, and knights continued to be expressed in a figural way, the elephant was somehow replaced with a bishop, while the rook seemed even more flexible, as demonstrated by the Lewis chessmen's famous "berserker" warders of Norse mythology, produced in the latter part of the 12th century, likely in Trondheim.

Meanwhile, the game itself once more steadily gained in popularity. When Alfonso X of Castile's (reign 1252 to 1284) famous Book of Games appears towards the end of the 13th century, chess is specifically given pride of place as "a nobler and more honoured game than dice or backgammon", with "chess" in this case simply meaning shatranj; indeed, Alfonso's book cites many of the Arabic manusbat.

Even more significantly, the allegorical potential of chess began to be increasingly featured throughout a remarkably wide variety of medieval literature, from the romances of Les Échecs Amoureux, Perceval, Walewein, Huon de Bordeaux, and many more, to Jacobus de Cessolis' famous political morality book, Liber de moribus hominum et officiis nobilium super ludo scachorum, where an impetuous king is taught the game of chess to learn how to better govern the separate, interconnected interests of his kingdom.

At some point in the late 15th century, the rules of chess underwent a transformative change: the bishop was allowed to travel to any free square along an open diagonal, while the queen was suddenly transformed into by far the most powerful piece on the board, with a movement that combined both the rook and the new bishop. This new form of the game, referred to as "queen's chess" or even "mad chess", rapidly swept through Europe, comprehensively replacing its vastly slower 1000-year-old predecessor in little more than a generation or two.

As the game's new principles began to be rigorously studied in earnest, expert players correspondingly emerged who had famously mastered them: legendary names such as Ruy Lopez, Paolo Boi, Giovanni Leonardo da Cutri, and Gioachino Greco, internationally renowned chess masters who wrote books, played blindfolded, and thrilled princes and kings throughout major European courts with their brilliant play.

While chess was still often associated with romance, the focus subtly shifted from its medieval use as a proxy for a well-ordered society to glowing tributes and descriptions of the game itself, starting with the late 15th-century poem Scachs d'amor, 64 stanzas describing the courtship of Venus by Mars through a chess game according to the new rules. This was shortly followed by Marco Girolamo Vida's influential Latin poem Scacchia Ludus, where the new game was provided with a classical origin myth befitting its station through the telling of a chess game between Apollo and Mercury on Mount Olympus in Virgilian hexameters. Scacchia Ludus inspired several imitators over the years, most famous of which was William Jones' English poem The Game at Chess, over 200 years later, where Caïssa, the "goddess of chess" is introduced.

Of course, the broader allegorical use of chess hardly ended overnight. From Rabelais' chess ballet in his Cinquième livre to Saint Teresa of Avila detailing in The Way of Perfection how nuns could harness their humility to "checkmate the divine king" to William Shakespeare's famous chess scene between Ferdinand and Miranda in The Tempest to Thomas Middleton's political satire A Game at Chess, chess imagery continued to be used to express a wide range of topics. But something had changed: the more advanced chess play came to be appreciated as something that could be acquired through patient and deliberate study, the more it took on the air of a specialized craft rather than a metaphor to reflect broader societal concerns.

When Baldassare Castiglione's bestselling Book of the Courtier was published in the early-16th century, competency in the new chess was explicitly acknowledged to require "as much study as if he would learn some noble science or do anything else of importance", leading one of the characters to conclude that, when it comes to chess, "mediocrity is more praiseworthy than excellence," a sentiment vitriolically echoed some 50 years later by Michel de Montaigne, whose bitter denunciations of the misspent time required to develop expertise at such a puerile game seem clearly tinged with a sense of personal disappointment (108).

By the turn of the 18th century, chess's universally recognized computational sophistication made it particularly resonant with the dawn of the Age of Enlightenment. In the wake of Newton's transformative insights, many were convinced that all of our problems could be similarly dealt with through a dispassionate combination of reason and knowledge.

It was a view vividly incarnated in the great Encyclopedia project of Denis Diderot (1713 to 1784) and Jean-Baptiste le Rond d'Alembert (1717 to 1783) that strove to establish a baseline of all human knowledge within one single work so as to create the appropriate conditions for a rational-based, scientific civilization that would duly lead us out of the darkness of superstition and fear and into the light. Others, however, such as Jean-Jacques Rousseau (1712 to 1778), famously disagreed, claiming that by needlessly shackling ourselves to the so-called institutions of civilization, we have become unnatural, unhappy, and wicked.

And what is particularly intriguing for our story is that, somehow, both of these views – one wholly aligned with the formal rigours of science and technology and the other a Romantic assertion of the creative powers of human emotion and desire – have so strongly overlapped with chess right from their outset. Rousseau was a dedicated chess player, and both he and Diderot were regulars of Café de la Régence in Paris, the epicentre of the chess world and home to the brilliant Philidor, the world's most dominant chess player, explicitly mentioned in Diderot's wide-ranging philosophical dialogue Rameau's Nephew, which is set in that very café.

Meanwhile, chess-related problems such as The Knight's Tour began to be pondered by professional mathematicians trying to find a way for a knight to move directly to all 64 of the squares on a chessboard without repeating itself. The puzzle had been explicitly treated in ancient Arabic chess manuscripts as well as some Indian mathematical treatises before becoming 'rediscovered' in the 18th century by French mathematicians largely ignorant of the previous work. Ultimately, it was left to the renowned Swiss mathematician Leonhard Euler (1707 to 1783) to make a rigorous study of the matter, which he presented to the Academy of Sciences in Berlin in 1759.

Perhaps the greatest harbinger of chess's future scientific influence occurred for something that was not actually science at all: the so-called "Mechanical Turk" chess-playing automaton designed by Wolfgang von Kempelen (1734 to 1804), which actually contained a highly-skilled human player lodged within it. The Turk toured the courts of Europe for decades, playing against some of the world's most famous people, defeating both Benjamin Franklin (1706 to 1790) and Napoleon Bonaparte (1769 to 1821).

In 1820, the alleged automaton beat 28-year-old Charles Babbage, the English polymath who's widely regarded as the father of computer science. Babbage had long been fascinated by automata, and while he seemed quite certain that the Turk was controlled by a human, the experience further piqued his burgeoning interest in developing mechanical calculating devices based upon his groundbreaking Analytical Engine.

Meanwhile, the skills of the world's best chess players continued to progress. In the 1850s, Paul Morphy, an even greater talent than Philidor, suddenly arrived on the scene from America. Morphy, who comprehensively defeated virtually every player he faced, captivated everyone with a beautifully elegant style of play that came to be known as the height of chess' "Romantic" style. Morphy was succeeded by the Bohemian William Steinitz, who became recognized as the first "world chess champion" 15 years after Lewis Carroll (1832 to 1898), an Oxford mathematician, published Through the Looking Glass, and What Alice Found There, a groundbreaking, chess-inspired work of literature.

Throughout the 20th century and beyond, chess's role as a "scientific drosophila" veritably exploded throughout a wide variety of domains, from psychology to game theory to linguistics, led by some of the greatest names in their respective field (Alfred Binet, Ernst Zermelo, Ferdinand de Saussure).

At the top levels of international competition, Emanuel Lasker (1868 to 1941) dethroned Wilhelm Steinitz (1836 to 1900) as world chess champion in 1894 and remained undefeated for a remarkable 27 years, until 1921, before being finally toppled by the charismatic Cuban José Raúl Capablanca (1888 to 1942). As top-flight players received increasing amounts of publicity, tales of "chess addiction" began to abound, led by the French artist Marcel Duchamp (1887 to 1968), who at one point publicly announced that he would give up art for chess.

Chess's unique combination of intense competition and rigorous analysis had always had the power to provoke obsessive behavior in its followers, but now that it was viewed as a psychological sport fit for the brightest minds, growing numbers fell under its spell, particularly in places such as the newly formed Soviet Union, where the game that Vladimir Lenin (1870 to 1924) himself felt so passionately about was so actively promoted, as highlighted in the 1925 short film, Chess Fever. Writers, correspondingly, increasingly turned to chess as an ideal vehicle to address related themes of genius, madness, and the human capacity for obsession, led by the likes of Vladimir Nabokov (The Luzhin Defense), Stefan Zweig (Chess Story), and Samuel Beckett (Murphy).

At the top professional level, the competition kept getting fiercer. Capablanca was succeeded by the dominant Russian-born French émigré Alexander Alekhine (1892 to 1946), who was world champion from 1927 to 1935 and from 1937 to 1946, punctuated only by an unexpected loss to Max Euwe (1901 to 1981) in 1935. After Alexhine's death in 1946, Soviet chess players (Mikhail Botvinnik, Vasily Smyslov, Mikhail Tal, Tigran Petrosian, Boris Spassky) had a stranglehold on the title until America's Bobby Fischer (1943 to 2008) famously beat Spassky in the highly publicized 1972 World Championship that firmly established chess as a sport in the public consciousness.

Meanwhile, psychologists and computer scientists like Alan Turing, Claude Shannon, and Herbert Simon had been actively using the notion of a high-level chess-playing computer as the primary benchmark for artificial intelligence for decades, with the celebrated breakthrough in 1997 when IBM's "Deep Blue" won a widely-publicized match against then-world champion Garry Kasparov (1963-). Within ten years of that event, chess computers (called "chess engines") became widely recognized as consistently unbeatable by the best human players, and are now regularly used as analysis and training tools by all serious players.

Magnus Carlsen, the world's current #1 player and widely considered to be one of the best players of all time, has spent all of his professional career in an era when no human could beat the best chess engine. But the dominance of chess engines has hardly dented the global popularity of this storied game, which has emphatically adapted to the internet age. Today, far more people play online than over the board, and websites routinely host hundreds of thousands, if not millions, of people playing chess every day.