A Short History of Dominoes: From Chinese Tiles to the Browser

Most short histories of dominoes open with a Chinese emperor, a date around 1120, and a set of tiles found in an Egyptian tomb. This one does not, because none of those claims survives a request for evidence. What can be said with confidence is smaller and more useful: there are two distinct families of domino tile, they are built differently, and the one used on this site is the younger of the two. The rest of this article separates what is documented from what is merely repeated, and says which is which.

Two families of tile, not one

The tiles you can pick up and count today fall into two families. The Chinese family is the older and has 32 tiles. The European family, the one this site uses, has 28. They are often described as one game that travelled west and lost four tiles on the way. They are better understood as two different objects that happen to share the idea of a rectangle with pips at each end.

The Chinese set

A Chinese set has no blanks. Every face shows between one and six pips, so there are only 21 distinct tiles to make: six doubles and fifteen mixed tiles. To reach 32, eleven of those tiles are included twice. The duplicated eleven form the civil suit, and the ten single tiles form the military suit. Within the military suit, tiles are grouped in pairs by pip total: 6-3 pairs with 5-4 because both total nine, 6-2 with 5-3 (eight), 5-2 with 4-3 (seven), and 4-1 with 3-2 (five). The last two military tiles, 4-2 and 2-1, are paired with each other even though their totals differ. Civil tiles carry traditional names, the double-six being "heaven" and the double-one "earth". The games played with this set rank tiles and pairs against each other rather than matching pips along a line; they are covered in one paragraph of the variations article, so this article does not explain them.

The European set

A European double-six set contains every pairing of the numbers 0 to 6, each exactly once. Seven of those pairings are doubles and 21 are mixed, for 28 tiles in all. The blank is a full member of the set: seven tiles carry at least one blank, and the double-blank is a legal opening tile if it is the highest double anyone holds, which happens only when nobody holds any other double. Nothing is duplicated and there are no suits. The whole structure of the game played here, from the seven-tile deal to the pip count that decides a blocked hand, follows from this one-of-each design; the arithmetic is worked through in the mathematics article.

One arithmetic coincidence is worth noticing because it explains why the two families get confused. Take a European set and remove every tile with a blank. Seven tiles go: the double-blank and the six mixed tiles 0-1 to 0-6. The 21 that remain are exactly the 21 distinct tiles a Chinese set is built from. The Chinese set then adds a second copy of eleven of them; the European set adds the seven blanks instead. Both routes start from the same 21 tiles and arrive at different totals, 21 + 11 = 32 on one side and 21 + 7 = 28 on the other.

Two stories that circulate without evidence

The emperor and the year 1120

The most repeated origin story says that dominoes were invented, or presented to the Emperor Huizong (older spellings give Hui Tsung), in about 1120. Some versions name the inventor, some say the set was found in his tomb, and some give the exact year 1120 without saying where it comes from. No tile, painting, inventory or dated text from that period has been produced to support any version. An earlier edition of this article repeated the tomb version too, and has been corrected. The most that can be said is that Chinese tile sets are considerably older than the European ones, and that the 1120 figure is a tradition, not a measurement.

The tomb of Tutankhamun

A second story places a set of dominoes in the tomb of Tutankhamun. The tomb was excavated in the 1920s and its contents were catalogued item by item; the records are published and searchable. They list board games, which is probably how the story started, but no dominoes. The claim appears to have been copied from one popular source to the next until repetition made it look like consensus. If a page tells you the pharaoh played dominoes, that page has not checked.

How to tell the difference yourself

A claim about the age of a game is worth something when it points at an object or a document: a surviving set with a known findspot, a dated rulebook, a painting that shows the tiles. A claim that points only at another website, or at "historians" with no names, is a claim being passed along. The two stories above fail that test. For a general account of tile games written to that standard, David Parlett's The Oxford History of Board Games (1999) is the usual starting point.

What is documented: the European set in the eighteenth century

The 28-tile set with blanks is first recorded in Italy and France in the eighteenth century. How it relates to the Chinese set is not established. It is often written that traders or missionaries carried the game west along a named route, but no document records such a transfer, and the structural differences above are large enough that independent invention cannot be ruled out. This article therefore gives no transmission route. It gives a place and a century, which is what the record supports.

The word itself is not settled either. The usual suggestion connects it to the black hooded cloak and mask called a domino, worn at masquerades, on the grounds that the tiles are black-backed with white faces. It is a plausible guess and it is presented here as one. Nobody has produced a document that shows the name being coined.

What did spread, over the following two centuries, was a family of matching games played with the European set. They differ mainly in what happens when a player cannot match either open end. In the game played on this site, that player simply passes; any tiles set aside after the deal stay out of play for the whole hand. Games in which a stuck player takes a tile from the set-aside pile instead are a different variant, Draw Dominoes, and the difference changes everything about how you read an opponent, because in the blocking game a pass is permanent information. The ruleset used here is written out in full on the rules page.

From a table to a browser

It would be natural to end with the date of the first computer version of dominoes. This article does not, because any date given would be a guess dressed as a fact, which is the habit this article is trying to break. What can be described precisely is what a browser version of the game consists of, since the code for this one can be read.

The set is a list of 28 number pairs. Shuffling is a random reordering of that list, after which each seat takes seven entries and the remainder, if any, is never touched again. The line of play is a list of placed tiles, and the two open ends are read off its first and last entries rather than stored separately. The rule that a tile must match an open end becomes a comparison of two numbers. The rule that the highest double opens becomes a search across all hands for the largest double, falling back to the heaviest tile when no double was dealt. Nothing about this is clever; it is the same ruleset expressed as bookkeeping a machine can do.

The opponents are three fixed procedures. Easy plays the first legal tile in hand order. Medium scores each legal move for shedding doubles, shedding heavy tiles and keeping a flexible hand. Hard adds three things: setting both ends to the same number, favouring numbers that few unseen tiles still carry, and steering the ends toward numbers an opponent has already passed on. Measured over 6,000 simulated hands per matchup, Medium beats Easy 59.6% of the time, Hard beats Easy 63.2%, and Hard beats Medium 54.6%, each figure within about 0.6%. Those are the only numbers in this article that were produced by measurement, and they were produced by us.

Some things do not carry across. There is no click of tiles being shuffled, because the game has no audio at all. There is no second person at the table; the other seats are always the computer. The number of seats is not chosen by the player but by the width of the screen: four seats at 640 pixels and wider, two below that. A history that ended by claiming the browser version preserves the clatter and company of the table would be inventing things in the same way the emperor story does, just closer to home.

What to take from this

Two families of tile exist, and only one of them has blanks. The Chinese set is older, is built by duplication, and is played by ranking. The European set is first recorded in eighteenth-century Italy and France, is built one-of-each, and is played by matching. The emperor of 1120 and the pharaoh's tomb are stories without evidence. Everything else you read about the history of dominoes should be tested against that short list, and this article should be tested the same way.