Twenty-one rose to prominence in France in the 18th century and spread from there to Germany and Britain from whence it crossed to America.

Known initially as vingt-un in all those countries, it developed into pontoon in Britain after the First World War and blackjack in Canada and the United States in the late 19th century, where the legalisation of gambling increased its popularity.

[1][2] Just two years later, the first brief description of the game is given in a novella by Spanish author Miguel de Cervantes, most famous for writing Don Quixote.

Cervantes was a gambler, and the main characters of his tale "Rinconete y Cortadillo", from Novelas Ejemplares, are a couple of cheats working in Seville.

They are proficient at cheating at veintiuna (sic), and state that the object of the game is to reach 21 points without going over and that the ace scores 1 or 11.

This short story was written between 1601 and 1602, implying that ventiuna had been played in Castile since the beginning of the 17th century or earlier.

[4] It was also played at the court of Louis XV and is reputed to have been the favourite card game of Napoleon,[5] but no French rules appear until 1817, nearly two decades after their publication in England.

In Britain, the game is also recorded in the 1770s and 1780s, for example in a comedy entitled Dissipation,[8] but the first rules appear in the 1800 edition of Hoyle's under the name of vingt-un.

[9][10] Known in the German-speaking world as Siebzehn und Vier ("seventeen and four"), Einundzwanzig ("twenty-one"), Hop(p)sen, Hoppm,[11] Rathen or, frequently, by its original French names of vingt-un or vingt-et-un, the game had spread to Prussia and the Austro-Hungarian Empire there by the second half of the 18th century,[12] and had become a universally common game of chance by 1854.

[14] There is a popular myth that, when vingt-un was introduced into the United States in the early 1800s – other sources say during the First World War and still others the 1930s – gambling houses offered bonus payouts to stimulate players' interest.

This hand was called a "blackjack", and it is claimed that the name stuck to the game even though the ten-to-one bonus was soon withdrawn.

Since the term "blackjack" also refers to the mineral zincblende, which was often associated with gold or silver deposits, he suggests that the name was transferred by prospectors to the top bonus in the game.

He was unable to find any historical evidence for a special bonus for having the combination of an ace with a black jack.

The following sections give an outline of the regional variants of twenty-one beginning with the early rules in France which are probably close to the original game.

The dealer may also draw additional cards and, on taking vingt-un, receives double stakes from all who stand, except those who also have 21, with whom it is a drawn game.

[7][16] English vingt-un later developed into an American variant in its own right which, during the Klondike Gold Rush (1896–99) became known as blackjack (see below).

The banker (banquier or bankhalter) places a fixed or variable stake, shuffles the cards well and has one of the punters or pointeurs cut them.

The name dates back to the First World War and is probably a corruption of 'vontoon', which in turn derived from vingt-un, but the game is clearly much older.

In addition to different terminology and payment systems, there are other nuances, such as splitting pairs, insurance and doubling down which add to the skill of the game.