History of blackjack

Blackjack is the American descendant of a European family of twenty-one games whose paper trail starts in Spain around 1601 and runs through 18th-century France, the English Hoyle’s of 1800, and the Nevada casinos licensed from 1931. The game you see dealt today, with a 3:2 natural, a fixed dealer drawing rule and a published best strategy, is much younger: its mathematics date from 1956 and 1962, and most of its rule variations are reactions to that mathematics.

From veintiuna to vingt-un

The oldest surviving reference to a game whose object is to reach 21 without exceeding it is literary. Miguel de Cervantes’s novella Rinconete y Cortadillo, written in 1601–1602, describes a pair of card cheats in Seville who play veintiuna, counting the ace as either 1 or 11. A 1611 Spanish dictionary names veinte y uno as a card game. Both references are set out in the Wikipedia history of Vingt-Un, which notes the game was played with the Spanish baraja pack rather than the 52-card French pack.

The French name vingt-un (later also written vingt-et-un) is first recorded in a 1768 Mercure de France entry that calls the game fashionable but “very old”. It is said to have been played at the court of Louis XV and to have been a favourite of Napoleon; those are traditions reported by the same source rather than documented facts. The first French rulebook dates only from 1817, after the English had already printed theirs.

In Britain the game appears in the 1770s and 1780s, and the first printed rules were in the 1800 edition of Hoyle’s. The British branch later grew into pontoon after the First World War. In German-speaking Europe the same game was Siebzehn und Vier (“seventeen and four”) or Einundzwanzig.

Arrival in America and the name “blackjack”

Twenty-one reached the United States in the early 1800s. The first American rules, printed in 1825, simply reprinted the 1800 English Hoyle’s. The Wikipedia article on blackjack dates the renaming of the English game to “blackjack” to around 1899.

The commonly repeated explanation for the name is that early American gambling houses paid a 10-to-1 bonus when a player’s two-card 21 consisted of the ace of spades and a black jack (the jack of clubs or spades). The bonus was supposedly withdrawn once the game was popular but the name stuck. You will see that account in most blackjack books and on most casino websites. Card historian Thierry Depaulis rejects it: he found no evidence for an ace-of-spades-plus-black-jack bonus and instead traces the word to Klondike Gold Rush prospectors (1896–99), who applied “blackjack” to the top bonus hand of an ace with any ten-point card. Treat the 10:1 story as folklore unless a primary source turns up.

Nevada, 1931

Legal casino blackjack is a product of Nevada law. Wikipedia’s history of gambling in the United States records that in 1931 the state “legalized most forms of gambling when Assembly Bill 98 was signed into law”, providing revenue during the Depression. Growth was slow at first because Nevada’s population was small. By the post-war boom, twenty-one was a standard Las Vegas table game, dealt by hand from a single deck.

Those early single-deck games had rules that players would now consider generous. Las Vegas Advisor contributors recall the “old Las Vegas Strip rules” of the 1960s and 1970s, in which a single-deck, dealer-stands-on-soft-17 game gave a perfect basic-strategy player a tiny edge, and describe the 1980s Strip as still offering single- and double-deck games with the dealer standing on soft 17 (Las Vegas Advisor). None of those games exist in that form now; see how casino rules evolved.

1956: the first correct strategy

Until the 1950s nobody knew the right play for most hands. Four US Army enlisted men stationed at the Aberdeen Proving Ground in Maryland worked it out on desk calculators. Roger R. Baldwin, Wilbert E. Cantey, Herbert Maisel and James P. McDermott published “The Optimum Strategy in Blackjack” in the Journal of the American Statistical Association, volume 51, issue 275, pages 429–439, September 1956; the bibliographic record is held by Crossref. Their strategy was the first that was mathematically sound, and modern basic strategy differs from it only in a handful of doubling and splitting decisions. The story of the “Four Horsemen of Aberdeen” is told in its own article.

1962: Thorp and the end of innocence

Edward O. Thorp, a mathematics instructor at MIT, read the 1956 paper, re-ran the calculations on an IBM 704 computer and asked a new question: what happens to the player’s expectation as cards leave a single deck that is not reshuffled every hand? The answer, that the player holds an advantage when the remaining deck is rich in tens, became Beat the Dealer (1962). The Wikipedia biography of Thorp records that the book sold more than 700,000 copies and reached the New York Times bestseller list. Thorp’s role in both basic strategy and counting is covered in Edward Thorp and Beat the Dealer.

The shoe era

Casinos could not change the arithmetic, so they changed the conditions. The chief responses, in rough order, were more decks, earlier shuffles and shallower cut cards, restrictions on doubling and splitting, and eventually continuous shuffling machines. Four-, six- and eight-deck shoes became the norm for mass-market tables because every extra deck slightly raises the house edge and dilutes the information a counter can gather. Each later innovation, from the 6:5 natural payout to side bets and dealer-hits-soft-17, has the same character: a small adjustment that moves the edge toward the house without making the game look different to a casual player.

Meanwhile the analytical tradition continued. Julian Braun’s computer simulations refined strategy in the 1960s and 1970s; Peter Griffin’s The Theory of Blackjack (1979) formalised the mathematics; Stanford Wong, Arnold Snyder and Don Schlesinger built the counting literature. The Blackjack Hall of Fame, founded in 2002 and housed at Barona Resort & Casino near San Diego, now records the people involved (Blackjack Hall of Fame members).

Timeline

What the history tells a player

Three lessons follow from the record. First, “blackjack” has never been one fixed game: the rules you are dealt are a snapshot, so read the table placard rather than assuming. Second, the strategy you learn from a chart is not tradition but arithmetic, worked out in 1956 and confirmed by computer ever since; it does not depend on who is dealing or how the last hand went. Third, every rule change since 1962 has been priced. The house edge of any specific game, including the six-deck, dealer-stands-on-soft-17 game our strategy chart assumes, can be looked up or calculated, and that is the only honest basis for choosing a table.

Related reading

• The Four Horsemen of Aberdeen
• Edward Thorp and Beat the Dealer
• How casino blackjack rules evolved
• Blackjack rules