From Veintiuna to 21: A Short History of Blackjack

Blackjack's earliest known mention is in a Spanish story by Miguel de Cervantes written around 1601, where card cheats in Seville play veintiuna, "twenty-one". The game spread through Europe and reached America in the early 1800s as vingt-un. It took the name "blackjack" around 1899, probably from gold prospectors in the Klondike, and in 1956 four mathematicians worked out the strategy players still use today.

Seville, around 1601: veintiuna

In Rinconete y Cortadillo, one of Cervantes's Exemplary Novels, two young swindlers make a living cheating at cards in Seville. One of their games is veintiuna, where the aim is to reach 21 without going over and an ace counts as 1 or 11. If cheats were already playing it in the story, the game was well known in Spain by then.

Europe and the road to America: vingt-un

Versions of twenty-one spread through Europe under local names, including the French vingt-et-un. It was played in Britain by the 1770s, and the first written rules appeared there in 1800 as vingt-un. The first American rules, printed in 1825, were a reprint of the English ones. For most of the 19th century, Americans still called the game vingt-un or simply twenty-one.

Those early games were different from today's. The deal often passed between players, and the dealer had real advantages that modern rules have removed.

The Klondike, 1890s: "blackjack"

Ask most players why the game is called blackjack and you'll hear the same story: to attract players, early American gambling halls paid a 10 to 1 bonus for an ace of spades with a black jack, and the name stuck after the bonus disappeared.

It's a good story, and there's no evidence for it. The card historian Thierry Depaulis found no record of such a bonus. He traces the name to prospectors in the Klondike gold rush (1896 to 1899), who called their version of vingt-un "blackjack". Their bonus hand was an ace with any 10-value card, and the name may have come from blackjack, a miners' term for zincblende, a mineral found near gold and silver. Either way, by around 1899 the game had its modern name.

Las Vegas and the dealer's rule

When Nevada legalized gambling in 1931, blackjack became a casino game with a fixed house dealer, and the rule that defines it today took hold: the dealer has no choices, hitting to 16 and standing on 17. Players make every decision; the dealer makes none. That asymmetry is why the game can be studied mathematically, and why it eventually was.

1956: the Four Horsemen solve the game

In the early 1950s, four men serving at the U.S. Army's Aberdeen Proving Ground, Roger Baldwin, Wilbert Cantey, Herbert Maisel and James McDermott, spent about eight months calculating the best play for every hand on Army desk calculators. In September 1956 they published "The Optimum Strategy in Blackjack" in the Journal of the American Statistical Association.

It was the first mathematically sound basic strategy, and under the rules of 1950s casinos it made the game close to even, by later estimates even slightly in the player's favor (Las Vegas Advisor). Few gamblers read statistics journals, and casinos didn't notice. Blackjack players later nicknamed the four "the Four Horsemen of Aberdeen" (GGB Magazine).

1962: Thorp beats the dealer

A young mathematician, Edward O. Thorp, read the Baldwin paper and asked a new question: since cards leave the deck as they're played, does the advantage shift during a deal? In 1959, at MIT, he used an IBM 704 computer to work through the possibilities. He presented the answer, card counting, to the American Mathematical Society in January 1961 and published it in Beat the Dealer in 1962. The book sold over a million copies (UC Irvine Libraries).

Casinos reacted by adding decks and shuffling earlier, and card counting has been a cat-and-mouse game ever since. Whether it still works in the age of online play is the subject of Does card counting work online?

Today: one game, many tables

Modern blackjack looks much like the game the Four Horsemen solved: several decks, a dealer who stands on 17 (or, at some tables, hits soft 17), blackjack paying 3 to 2. The biggest change is where it's played. Online, the game moved first to single-player screens and then back to shared tables, closer to the social game Cervantes's swindlers were playing four centuries ago. We wrote about that pull in Multiplayer vs solo blackjack.

If you want to play it the way the mathematicians would, start with our basic strategy chart.

Sources

• Blackjack: History (Wikipedia), for the Cervantes reference, the English and American rule books, Depaulis's research and the Baldwin paper
• A Winning Hand: Edward O. Thorp (UC Irvine Libraries)